Assassins creed 2 and 3 are not entirely historically accurate. The game is based in the 1400’s and 1500’s. It is about a creed that has set out to destroy the templar army. Some of the people in the games are real people who lived in these time periods. Parts of the game are exactly as stated in historical records such as the bonfire that killed Savonarola.
The characters in the game are both historically correct and false characters. Characters like Lorenzo De Medici, the Borgia family (Including Cesare, Rodrigo and Lucrezia) and Leonardo Da Vinci existed in reality where as characters like La Volpe, Ezio Audatore, and Antonio did not. The game is based on real life people but an interesting new story has been added.
Secondly the Creed in the game had nothing to do with reality. The assassins did not exist but interestingly people were hired to kill Cesare Borgia but did not succeed. So the Assassins Creed could have been based on these attempts but in reality there was no Creed at all.
Thirdly the Templars are real but did not exist in this Time Period. The Templars were part of the crusader period. They pretty much ended after the 1200’s so Rodrigo Borgia was not a Templar. The Templars are in actual fact real but they weren’t part of the 1400’s or 1500’s.
Lastly the game mentions a piece of Eden which was not real at all. In the game the pieces of Eden were advanced technologies which were thought to be capable of bending the thoughts of one or more individuals the will of the user. These pieces are fake and have no connections to historical records.
The Game assassins creed is not entirely accurate but have resemblances to history and the time period its set in.