Fomemko is a Russian mathematician. He has worked with orbital maneuver computer programs to figure the positions of stars and planets in the past, and then lining up these constellations with historical data from these times to see if the observed astronomy matches their data of reverse movement of the stars.
So, in conclusion to his findings, he has decided that about 1,000 years of history do not actually exist. Thus, New Chronology was born.
http://en.wikipedia.org/wiki/New_Chronology_(Fomenko)
Some choice bits:
That Ancient Roman and Greek statues, showing perfect command of the human anatomy are fakes crafted in the Renaissance when, according to Fomenko, such command was for the first time attained;
That the Chinese tables of eclipses are useless for dating as they contain too many eclipses that did not take place astronomically; that Chinese tables of comets even if they were true can't be used for dating; (editors note: this statement is made because Chinese historians routinely watched and chronicled star movements, including comet appearances that match with computed reverse movements of the stars)
That there was no such thing as the Tartar and Mongol invasion followed by over two centuries of yoke and slavery because the so-called "Tartars and Mongols" were the actual ancestors of the modern Russians, living in a bilingual state with Turkic spoken as freely as Russian;
That archaeological dating, dendrochronological dating, paleographical dating, numismatic dating, carbon dating, and other methods of dating of ancient sources and artifacts known today are erroneous, non-exact or dependent on traditional chronology; that their use in conjunction as 'confiming' one another is a statistical fallacy - probabilities can't be added.
That there is not a single document in existence that can be reliably dated earlier than the 11th century; that most 'ancient' artifacts may find other than consensual explanation;
Also of note, the period of time that Fomemko wipes out would include the birth, rise and golden of age of Islam.