A lot of research has gone into the Assassin's Creed game design, actually about 9 months worth, so with all that research it is no wonder they decided to put out a book as well. Corey May has posted a great look at the research of he did in order to help design the game. Check it out here: ign.com;
where and when it would take place, who our hero would be, the tone, the characters, the major events, etc. Once all of that was settled, it was time to start doing research. All told, I spent about nine months just learning about the time period – no actual script writing took place. I was jotting down notes, creating massive timelines, brainstorming set piece locations and events, listing possible historical figures; stuff like that. I am committed to historical accuracy
‘I will seek Vengeance upon those who betrayed my family. I am Ezio Auditore da Firenze. I am an Assassin…’
Betrayed by the ruling families of Italy, a young man embarks upon an epic quest for vengeance. To eradicate corruption and restore his family's honour, he will learn the art of the assassins.
Along the way, Ezio will call upon the wisdom of such great minds as Leonardo Da Vinci and Niccolo Machiavelli – knowing that survival is bound to the skills by which he must live.
To his allies, he will become a force for change - fighting for freedom and justice. To his enemies, he will become a threat dedicated to the destruction of the tyrants abusing the people of Italy.
So begins an epic story of power, revenge and conspiracy.