Unfortunately no, he is just a fictitious character.
Conner
There are heaps They include Ezio The Jester The dentist and more but the main Brotherhood characters are Altair (From Assassins creed and Assassins creed Bloodlines) Ezio (Assassins creed 2 and Assassins creed Brotherhood) Devon a.k.a. Exio (Assassins creed Revelations) Conner (Assassins creed 3) And coming out soon Edward (Assassins creed IV: Black Flag) i hope this is useful if you want to impress people who don't know what Assassins Creed is (Wich is Impossible) so yeah
No
You play as Conner Kenway. The grandson of Edward Kenway from Black Flag.
You assume full control of Connor in Sequence 5 of the game.
You do get Assassins but not like the ones from the games, they don't follow a creed either. They are basically hired guns.
Yes
Yes there will be another Assassins creed Wich will be Edward Kennway ( Conner Kennways brother) It is a carry on from Assassins Creed 3. This game will be called Assassins creed IV: Black Flag
If you are talking about Altair in Assassins Creed, then no, he is not real. He is only real in game as a bar tender which his family before him were assassins.
The Knights Templar really did exist, from 1119 to 1312. They did participate in battles, however, they were not assassins.
For Assassins Creed 1 No, for Assassins Creed 2 yes.
No. He is a REAL historical figure that probably had no dealings with the assassins.