Students of the Middle Ages all know that the Holy Roman Empire was, in the words of Voltaire, 'neither holy, nor Roman, nor an empire'.
But did this agglomeration of medieval power and influence also saddle us with a bogus calendar?
Could an emperor – maybe two emperors, with the help of a friendly pope – have been responsible for shoving 297 years' worth of utterly fictitious history into our collective consciousness, there to fester and cause problems for innocent historical researchers? What year is it, anyway?
To be clear: the Phantom Time Hypothesis, originally by Heribert Illig and Hans-Ulrich Niemitz1, states that the Holy Roman Emperor, Otto III, in collusion with Pope Sylvester II, misdated the Western calendar in order to celebrate the end of the first millennium – 297 years early.
![]()
This theory claims that Otto and others then filled in the 'phantom time' with some pretty interesting, but totally imaginary, history.
What do tree rings tell us about a possible media conspiracy? What was Charlemagne – ideal ruler, or corporate myth? What secrets does the Aachen treasure room hold in addition to Jesus' underwear?
Inquiring minds want to know. The rest of you will just have to come along for the ride.
The Dark Ages - Who Turned Out the Lights?
The term 'Dark Ages' is in disrepute to describe the period between 500 and 1000 CE – Common Era. (For those unfamiliar with this politically correct term, the years are equivalent to 'Anno Domini', or 'AD'2).
During this period, it was formerly believed, Western Europeans did very little that would interest historians, or indeed anybody not directly related to them.
They produced almost no literature, art, or cultural artefacts. They made no appreciable progress in agriculture or technology. They didn't even have any interesting wars.
This bothered scholars.
What bothered them even more was that in the 7th, 8th, and 9th Centuries, there were no records to speak of.
Cities that one might assume to have been continuously inhabited, such as the German towns that were formerly Roman colonies, seem to have been empty of, say, market activity.
One could only conclude that, while there were obviously buildings there, churches and such, nobody ever came to town to sell a pig. Or at least, kept it a secret.
Then there were the Jews, who usually kept good community records. In the 6th Century, they were everywhere in Western Europe.
For about three centuries after that, they seem to have disappeared – only to show up again in exactly the same places. What could explain this? A shortage of parchment? A game of historical hide-and-seek?
By the 1980s, some people were taking a look at these historical puzzles, and asking themselves a few questions:
In a number of fields – archaeology, history, palaeography – scholars had questions. Faced with the obvious answer that 'we don't know, it just happened', they wrote their studies around the puzzles – until someone challenged their assumptions.
The resulting mini-firestorm of discussion has not resulted in a movement to change the calendar from 2011 to 1714, but the Phantom Time Hypothesis, as it came to be called, has provided food for thought.
![]()
The Least You Need to Know about the Middle Ages
Before examining the claims of the Phantom Time Hypothesis, it is well to review the following unquestioned facts about the Middle Ages:
![]()
The Phantom Time Hypothesis - An Outrageous Conspiracy Theory?
The Phantom Time Hypothesis, as advanced by German researcher Heribert Illig, and expanded by Dr Hans-Ulrich Niemitz of the Hochschule für Technik, Wirtschaft und Kultur in Leipzig, claims the following:
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Charles the Great as Media Invention?
The greatest surprise of the Phantom Time Hypothesis is the assertion, by Niemitz and others, that Charlemagne was an invented character who lived in an imaginary time.
This claim startles at first – after all, Charlemagne was the subject of no fewer than two medieval biographies (although both were written after his death).
Inventing heroes is hardly a new human enterprise, but Otto III not only revered Charlemagne, he found his body.
According to Otto Lomello, who was there when the tomb of the great Carolingian was opened in the numinous Year of Our Lord 1000:
Allegedly, other emperors later visited this tomb. In 1165, Friedrich Barbarossa removed the remains and had them interred in a sarcophagus (allegedly) belonging to Caesar Augustus.
Friedrich II (allegedly) put the bones in a casket of gold and silver. (He put something in there, but at this point, it is not safe to say what12.)
People visit these relics of Charlemagne in Aachen, just as they visit the other great Aachen relics, the ones which are displayed every seven years: St Mary's cloak, Christ's swaddling (baby) clothes, St John the Baptist's beheading cloth, and Christ's loincloth (or undergarment).
Perhaps it requires a conspiracy theory to doubt the authenticity of these items. Perhaps not. If one can be invented, cannot the other?
Reputable historians, of course, assume Charlemagne to have been a real person – an amazingly talented king who expanded the Frankish empire and accomplished many wonderful things.
Historian Will Durant, while acknowledging the legends surrounding this 'greatest of medieval kings', considers his battles and social reforms in detail.
Durant describes Charlemagne this way:
'He was of German blood and speech, and shared some characteristics of his people – strength of body, courage of spirit, pride of race, and a crude simplicity many centuries apart from the urbane polish of the modern French13.'
Could the truth about this greatest king since Arthur lie somewhere in between total acceptance of the received version, and the assumption that the monarch was invented out of whole cloth?
Much more research would be needed – and the past is a dodgy character, kind of hard to pin down.
![]()
What Difference Does It Make?
What difference does it make if the Phantom Time Hypothesis is real? None at all. Calendars will still bear a date in the 21st Century. No one will be sued.
It is extremely doubtful that anyone will suggest that Otto III be burned in effigy, or that the Kaiserdom in Aachen be desanctified.
It makes no difference at all. If the Holy Roman Emperor sneaked in 297 years' worth of made-up history, the only people who will care are a handful of medievalists, who might possibly say, 'Oh, that's why I can't find the sheep count.'
It makes no difference, because timekeeping is a social construct. There is no Y2K problem here. The planet moves as it moves, independent of Western notions of marking the days.
It is an interesting conundrum, however, and one that might make the historian reflect that our works and pomps might not be as time-honoured as we think they are. The distant past might not be as distant as we imagine.
Oh, and a lot of our ancestors were liars.
![]()
Read for Yourself
To follow the argument for the Phantom Time Hypothesis, read 'Did the Early Middle Ages Really Exist?' by the late Prof Dr Hans-Ulrich Niemitz.
Those who wish to investigate more deeply, and who can read German, may enjoy this web page, entitled 'Fantomzeit', by Fabian Fritzsche.
Don't read German? How about that elegant amalgam of German syntax and English vocabulary (well, sort of) that proliferates on the internet?
A little patience and good will renders this charming addition to the discussion both informative and suggestive for further research.
For a thorough discussion of the architectural issues involved (as well as a tour of the calendar problem from Julius Caesar on), see 'The Invented Middle Ages' by Heribert Illig.
Refutations of the Phantom Time Hypothesis have not actually been very thorough or painstaking, being mostly of the scornful variety. Most arguments available online, at any rate, are nicely summed up in this article on the 'Straight Dope' site.
Although the Phantom Time Hypothesis meets with general disbelief on the part of official scholarship (perhaps because this theory meets with general disbelief), it is difficult to find accessible texts that explain in detail why it is unlikely to be true.
For a more serious negative critique of the Phantom Time Hypothesis, you may need to read German (again).
Physicist Stephan Matthiesen's commentary, Erfundenes Mittelalter - fruchtlose These! [transl. 'Invented Middle Ages? A Fruitless Thesis!'], which appeared in the journal Skeptiker in 2001, offers refutations of major points of the theory as put forth by Heribert Illig, and characterises Illig's writing style as 'tiresome' ('ermüdend').
In this article, Matthiesen is replying specifically to Illig's version of the theory, and not to Niemitz's. Whether scholars will continue to take the time to refute this theory, or merely move on to other questions, remains to be seen.
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But did this agglomeration of medieval power and influence also saddle us with a bogus calendar?
Could an emperor – maybe two emperors, with the help of a friendly pope – have been responsible for shoving 297 years' worth of utterly fictitious history into our collective consciousness, there to fester and cause problems for innocent historical researchers? What year is it, anyway?
To be clear: the Phantom Time Hypothesis, originally by Heribert Illig and Hans-Ulrich Niemitz1, states that the Holy Roman Emperor, Otto III, in collusion with Pope Sylvester II, misdated the Western calendar in order to celebrate the end of the first millennium – 297 years early.
What do tree rings tell us about a possible media conspiracy? What was Charlemagne – ideal ruler, or corporate myth? What secrets does the Aachen treasure room hold in addition to Jesus' underwear?
Inquiring minds want to know. The rest of you will just have to come along for the ride.
The Dark Ages - Who Turned Out the Lights?
The term 'Dark Ages' is in disrepute to describe the period between 500 and 1000 CE – Common Era. (For those unfamiliar with this politically correct term, the years are equivalent to 'Anno Domini', or 'AD'2).
During this period, it was formerly believed, Western Europeans did very little that would interest historians, or indeed anybody not directly related to them.
They produced almost no literature, art, or cultural artefacts. They made no appreciable progress in agriculture or technology. They didn't even have any interesting wars.
This bothered scholars.
What bothered them even more was that in the 7th, 8th, and 9th Centuries, there were no records to speak of.
Cities that one might assume to have been continuously inhabited, such as the German towns that were formerly Roman colonies, seem to have been empty of, say, market activity.
One could only conclude that, while there were obviously buildings there, churches and such, nobody ever came to town to sell a pig. Or at least, kept it a secret.
Then there were the Jews, who usually kept good community records. In the 6th Century, they were everywhere in Western Europe.
For about three centuries after that, they seem to have disappeared – only to show up again in exactly the same places. What could explain this? A shortage of parchment? A game of historical hide-and-seek?
By the 1980s, some people were taking a look at these historical puzzles, and asking themselves a few questions:
- Why was there a three-century moratorium on building projects in Constantinople, of all places?
- Is it reasonable to assume that Romanesque architecture was created more than half a millennium after the fall of the Roman Empire? Or that the Cathedral of Aachen was 200 years ahead of its time in innovation?
- Where did everybody go?
The resulting mini-firestorm of discussion has not resulted in a movement to change the calendar from 2011 to 1714, but the Phantom Time Hypothesis, as it came to be called, has provided food for thought.
The Least You Need to Know about the Middle Ages
Before examining the claims of the Phantom Time Hypothesis, it is well to review the following unquestioned facts about the Middle Ages:
- Literacy was not widespread. Since most people could not read or write, the ability to do so equalled power. You could write down anything you liked, as long as your fellow literates did not challenge you.
- There are thousands of recognised forgeries from the Middle Ages. People forged wills, history texts, land deeds, etc, etc. In these cases, it is usually fairly easy to answer the question cui bono?3
- Although it may seem counterintuitive, one of the biggest forgery factories during this period was the Church.
- In this connection, it is well to mention the Donation of Constantine, a document which alleges that the Emperor Constantine (272-337 CE) died and left the pope in charge of vast amounts of land in Europe.
- The usual date for this forgery is the 8th Century CE (if there was an 8th Century CE).
- The Church did not only forge documents. Many, many churches throughout European Christendom have objects called relics – items which are said to have belonged to especially holy people, called saints, or to famous personages from the Christian Bible.
- These items range from artefacts and utensils, such as the chains used to bind St Peter or the Crown of Thorns4, to more personal things such as body parts (John the Baptist's head) and drops of blood5.
- To accept every single one of these objects as genuine is a matter of faith. To question the chain of evidence in their provenance – could these really be the bones of the Magi in that box? – is a question of forensic science and, one might claim, common sense.
- Churches at this time vied hotly for the possession of relics. A recognised relic was a sign of legitimacy for the owner. They were not above stealing these things from one another
- Nobody at this period owned a clock. To find out what day it was, they asked a priest. It was the Feast Day of Saint So-and-So. This was either a working day, or a holiday. That ended the discussion.
The Phantom Time Hypothesis - An Outrageous Conspiracy Theory?
The Phantom Time Hypothesis, as advanced by German researcher Heribert Illig, and expanded by Dr Hans-Ulrich Niemitz of the Hochschule für Technik, Wirtschaft und Kultur in Leipzig, claims the following:
- The Byzantine Emperor Constantine VII caused his scribes to recopy Byzantine historical documents from the old writing style, called majuscule, into the new writing style, called minuscule. Once this was done, the old books were destroyed.
- These facts are not in dispute. The Phantom Time Hypothesis claims that this undertaking provided a tempting opportunity to rewrite history – a temptation that Constantine VII did not resist.
- Holy Roman Emperor Otto III (related to Constantine VII through his, Otto's, mother, Theophanu), in connivance with Pope Sylvester II (né Gerbert d'Aurillac), decided to convince everybody they were living at the end of the First Millennium, because it was a wonderful opportunity for positive PR. Besides, Otto liked the idea of reigning in the Year 1000. It was such a nice, round number.
- The fact that these leaders moved the calendar by 297 years made it possible to invent an entire dynasty – to wit, the Carolingian period. Otto III modelled his reign after that of his 'hero', Charles the Great. If the Phantom Time Hypothesis is true, Charlemagne is as fictional as Prester John6.
From the evidence, it is obvious that Constantine, Otto, and Sylvester had means, motive and opportunity to perpetrate what they may not have regarded as a crime. But is there any evidence that they did so?
Although there is no 'smoking gun' in the form of, say, a confession – they would hardly have left a notarised statement lying about – there are some suspicious facts. One of these is the whole controversy between the Julian and Gregorian calendars.
Heribert Illig first noticed that when the Gregorian calendar was introduced in 1582, it was necessary to omit ten days to make up for the fact that the old Julian year was actually about ten minutes too long7.
These ten days (and a few more omitted since 1582) account for the reason Russian Christmas is later than Western Christmas8.
However, calculations based on the year that the Julian calendar was introduced (45 BCE) suggest that it should have been 13 days, not 10.
The figure of 10 suggests that the Julian calendar had been in operation for about 340 years less than the 1,626 years you would expect to find between 45 BCE and 1582 CE. Perhaps there is something wrong with the count of these years?
On the other hand, if the calendar had been correct in 325 CE, then ten days would be the correct number to omit.
As the detractors of the Phantom Time Hypothesis theory point out, this happens to be the date of the Nicene Council, which had so much trouble figuring out when Easter was.
The detractors figure that settles that – they claim the Gregorian calendar makers were only trying to get the calendar to agree with the state of affairs back in the 4th Century, when they first set the Easter date (though not without a lot of arguing).
Not so, replied Professor Niemitz, who points out that there is a problem with the placement of the equinoxes as well as the date of Easter:
Some historians have noticed this contradiction, but they solve it this way: the scholars in Caesar's time reckoned a different date for the equinox (the day in spring, where day and night have the same length). Yet it can be proved that the Romans used the same date for the equinox as we do today, i.e. the 21st of March. — from 'Did the Early Middle Ages Really Exist?' by Hans-Ulrich Niemitz.
That, of course, is not that. Those who oppose having their minds messed with by inquiring Germans have raised other objections to the Phantom Time Hypothesis. Phantom Time Hypothesisers have replied to them. Let the reader judge.
Although there is no 'smoking gun' in the form of, say, a confession – they would hardly have left a notarised statement lying about – there are some suspicious facts. One of these is the whole controversy between the Julian and Gregorian calendars.
Heribert Illig first noticed that when the Gregorian calendar was introduced in 1582, it was necessary to omit ten days to make up for the fact that the old Julian year was actually about ten minutes too long7.
These ten days (and a few more omitted since 1582) account for the reason Russian Christmas is later than Western Christmas8.
However, calculations based on the year that the Julian calendar was introduced (45 BCE) suggest that it should have been 13 days, not 10.
The figure of 10 suggests that the Julian calendar had been in operation for about 340 years less than the 1,626 years you would expect to find between 45 BCE and 1582 CE. Perhaps there is something wrong with the count of these years?
On the other hand, if the calendar had been correct in 325 CE, then ten days would be the correct number to omit.
As the detractors of the Phantom Time Hypothesis theory point out, this happens to be the date of the Nicene Council, which had so much trouble figuring out when Easter was.
The detractors figure that settles that – they claim the Gregorian calendar makers were only trying to get the calendar to agree with the state of affairs back in the 4th Century, when they first set the Easter date (though not without a lot of arguing).
Not so, replied Professor Niemitz, who points out that there is a problem with the placement of the equinoxes as well as the date of Easter:
Some historians have noticed this contradiction, but they solve it this way: the scholars in Caesar's time reckoned a different date for the equinox (the day in spring, where day and night have the same length). Yet it can be proved that the Romans used the same date for the equinox as we do today, i.e. the 21st of March. — from 'Did the Early Middle Ages Really Exist?' by Hans-Ulrich Niemitz.
That, of course, is not that. Those who oppose having their minds messed with by inquiring Germans have raised other objections to the Phantom Time Hypothesis. Phantom Time Hypothesisers have replied to them. Let the reader judge.
How Many Holes Are There in This Theory?
It's a very simple question, isn't it? How could anyone insert time into a chronology? We know how much time has passed since the death of Caesar, right? We can prove this independently? Let us see.
One way to check the date of things is by using radiocarbon dating to determine the age of artefacts. Detractors of the Phantom Time Hypothesis point this out, and say, 'Pish and tosh. We know how old things are from carbon dating.'
The problem with this: radiocarbon dating uses dendrochronology to calibrate itself, and dendrochronology has a few problems of its own.
Dendrochronology is dating things by examining tree rings. Trees lay down rings season by season. This growth varies according to prevailing conditions. If enough is known about the age of the tree, its location, conditions, etc, the wood can be used for dating.
Problems: there are not many trees that are old enough; there are not many trees of the same species; wood from buildings may have been lying around for a long time, may have been reused, etc.
It turns out that dendrochronologists have been using written sources to help 'correct' their timelines9.
This might be a problem if we want to use dendrochronology to correct a written source.
Another way to check the date of things is to go by the stars, which are not susceptible to falsification by ambitious emperors and clerics.
Unfortunately, the debate is still on as to whether written accounts of such phenomena as eclipses are accurate – or whether historians eager to correct their own timelines have been grasping at straws.
'This looks like Halley's comet, so it must have been that year...' The jury is still out as to whether this information can clear up the question. The research required would be massive.
Another objection to the Phantom Time Hypothesis is that Europe did not exist in a vacuum. If someone had changed the calendar, wouldn't anyone else – say the Muslims? – have noticed?
It is hard to say. Some areas of early Islamic history might actually be simplified by the discovery that the Western dates had been altered.
It might explain inscriptions on early Islamic coins – the ones that showed Muhammed meeting with a Persian emperor who supposedly died a century before. Similar claims are made about 'missing time' in Jewish records.
Another possible means of comparison would be Chinese history – which is notably long, with accurate astronomical observations10.
All these areas would require an enormous amount of research either to validate or refute the theory, research that is unlikely to be undertaken by anyone not interested in rewriting the timeline.
A theory is a theory because it is not an undisputed fact. A theory is a possible explanation. Does the Phantom Time Hypothesis fit this description? Yes.
Could it be definitively proven/disproven? Possibly. Is anyone interested enough to do the research? Time will tell.
It's a very simple question, isn't it? How could anyone insert time into a chronology? We know how much time has passed since the death of Caesar, right? We can prove this independently? Let us see.
One way to check the date of things is by using radiocarbon dating to determine the age of artefacts. Detractors of the Phantom Time Hypothesis point this out, and say, 'Pish and tosh. We know how old things are from carbon dating.'
The problem with this: radiocarbon dating uses dendrochronology to calibrate itself, and dendrochronology has a few problems of its own.
Dendrochronology is dating things by examining tree rings. Trees lay down rings season by season. This growth varies according to prevailing conditions. If enough is known about the age of the tree, its location, conditions, etc, the wood can be used for dating.
Problems: there are not many trees that are old enough; there are not many trees of the same species; wood from buildings may have been lying around for a long time, may have been reused, etc.
It turns out that dendrochronologists have been using written sources to help 'correct' their timelines9.
This might be a problem if we want to use dendrochronology to correct a written source.
Another way to check the date of things is to go by the stars, which are not susceptible to falsification by ambitious emperors and clerics.
Unfortunately, the debate is still on as to whether written accounts of such phenomena as eclipses are accurate – or whether historians eager to correct their own timelines have been grasping at straws.
'This looks like Halley's comet, so it must have been that year...' The jury is still out as to whether this information can clear up the question. The research required would be massive.
Another objection to the Phantom Time Hypothesis is that Europe did not exist in a vacuum. If someone had changed the calendar, wouldn't anyone else – say the Muslims? – have noticed?
It is hard to say. Some areas of early Islamic history might actually be simplified by the discovery that the Western dates had been altered.
It might explain inscriptions on early Islamic coins – the ones that showed Muhammed meeting with a Persian emperor who supposedly died a century before. Similar claims are made about 'missing time' in Jewish records.
Another possible means of comparison would be Chinese history – which is notably long, with accurate astronomical observations10.
All these areas would require an enormous amount of research either to validate or refute the theory, research that is unlikely to be undertaken by anyone not interested in rewriting the timeline.
A theory is a theory because it is not an undisputed fact. A theory is a possible explanation. Does the Phantom Time Hypothesis fit this description? Yes.
Could it be definitively proven/disproven? Possibly. Is anyone interested enough to do the research? Time will tell.
Charles the Great as Media Invention?
The greatest surprise of the Phantom Time Hypothesis is the assertion, by Niemitz and others, that Charlemagne was an invented character who lived in an imaginary time.
This claim startles at first – after all, Charlemagne was the subject of no fewer than two medieval biographies (although both were written after his death).
Inventing heroes is hardly a new human enterprise, but Otto III not only revered Charlemagne, he found his body.
According to Otto Lomello, who was there when the tomb of the great Carolingian was opened in the numinous Year of Our Lord 1000:
So we went in to Charles. He did not lie, as the dead otherwise do, but sat as if he were living. He was crowned with a golden crown and held in his gloved hands a sceptre; the fingernails had penetrated through the gloves and stuck out. Above him was a canopy of limestone and marble.
Entering, we broke through this. Upon our entrance, a strong smell struck us. Kneeling, we gave Emperor Charles our homage, and put in order the damage that had been done. Emperor Charles had not lost any of his members to decay, except only the tip of his nose.
Emperor Otto replaced this with gold, took a tooth from Charles's mouth, walled up the entrance to the chamber, and withdrew again. - Monumenta Germaniae Historica, Scriptores, VII, book III, 3211
Allegedly, other emperors later visited this tomb. In 1165, Friedrich Barbarossa removed the remains and had them interred in a sarcophagus (allegedly) belonging to Caesar Augustus.
Friedrich II (allegedly) put the bones in a casket of gold and silver. (He put something in there, but at this point, it is not safe to say what12.)
People visit these relics of Charlemagne in Aachen, just as they visit the other great Aachen relics, the ones which are displayed every seven years: St Mary's cloak, Christ's swaddling (baby) clothes, St John the Baptist's beheading cloth, and Christ's loincloth (or undergarment).
Perhaps it requires a conspiracy theory to doubt the authenticity of these items. Perhaps not. If one can be invented, cannot the other?
Reputable historians, of course, assume Charlemagne to have been a real person – an amazingly talented king who expanded the Frankish empire and accomplished many wonderful things.
Historian Will Durant, while acknowledging the legends surrounding this 'greatest of medieval kings', considers his battles and social reforms in detail.
Durant describes Charlemagne this way:
'He was of German blood and speech, and shared some characteristics of his people – strength of body, courage of spirit, pride of race, and a crude simplicity many centuries apart from the urbane polish of the modern French13.'
Could the truth about this greatest king since Arthur lie somewhere in between total acceptance of the received version, and the assumption that the monarch was invented out of whole cloth?
Much more research would be needed – and the past is a dodgy character, kind of hard to pin down.
What Difference Does It Make?
What difference does it make if the Phantom Time Hypothesis is real? None at all. Calendars will still bear a date in the 21st Century. No one will be sued.
It is extremely doubtful that anyone will suggest that Otto III be burned in effigy, or that the Kaiserdom in Aachen be desanctified.
It makes no difference at all. If the Holy Roman Emperor sneaked in 297 years' worth of made-up history, the only people who will care are a handful of medievalists, who might possibly say, 'Oh, that's why I can't find the sheep count.'
It makes no difference, because timekeeping is a social construct. There is no Y2K problem here. The planet moves as it moves, independent of Western notions of marking the days.
It is an interesting conundrum, however, and one that might make the historian reflect that our works and pomps might not be as time-honoured as we think they are. The distant past might not be as distant as we imagine.
Oh, and a lot of our ancestors were liars.
Read for Yourself
To follow the argument for the Phantom Time Hypothesis, read 'Did the Early Middle Ages Really Exist?' by the late Prof Dr Hans-Ulrich Niemitz.
Those who wish to investigate more deeply, and who can read German, may enjoy this web page, entitled 'Fantomzeit', by Fabian Fritzsche.
Don't read German? How about that elegant amalgam of German syntax and English vocabulary (well, sort of) that proliferates on the internet?
A little patience and good will renders this charming addition to the discussion both informative and suggestive for further research.
For a thorough discussion of the architectural issues involved (as well as a tour of the calendar problem from Julius Caesar on), see 'The Invented Middle Ages' by Heribert Illig.
Refutations of the Phantom Time Hypothesis have not actually been very thorough or painstaking, being mostly of the scornful variety. Most arguments available online, at any rate, are nicely summed up in this article on the 'Straight Dope' site.
Although the Phantom Time Hypothesis meets with general disbelief on the part of official scholarship (perhaps because this theory meets with general disbelief), it is difficult to find accessible texts that explain in detail why it is unlikely to be true.
For a more serious negative critique of the Phantom Time Hypothesis, you may need to read German (again).
Physicist Stephan Matthiesen's commentary, Erfundenes Mittelalter - fruchtlose These! [transl. 'Invented Middle Ages? A Fruitless Thesis!'], which appeared in the journal Skeptiker in 2001, offers refutations of major points of the theory as put forth by Heribert Illig, and characterises Illig's writing style as 'tiresome' ('ermüdend').
In this article, Matthiesen is replying specifically to Illig's version of the theory, and not to Niemitz's. Whether scholars will continue to take the time to refute this theory, or merely move on to other questions, remains to be seen.
WATCH THE VIDEO: