I tried Augustus first as well, knowing that the answer probably was Julius, since August *ought to be* the more famous of the two, and would be no doubt if not for Billy Shakespeare.
"Julius" was a surname, shared by Gaius's father, grandfather, uncle, cousins on his father's side, children, etc. It was not in any sense a "first" or "given" name.
No, Caesar never was an Augustus. He came before the empire, this cognomen was first given to his nephew Octavius, the first roman emperor. Anyway, I must complain : his last name was Julius (his gens), his first name was Gaius/Caius, and Caesar was a nickname (in latin a cognomen). This is a very common mistake... And another mistake is of course Franz Ferdinand ! His family name is Habsburg or von Österreich-Este, while his first name is "Franz Ferdinand"... Finally, Ataturk is not a last name but, once again, a nickname. His true name is Mustafa Kemal (but ok, Mustafa is indeed his first name).
Hmm. I always thought Ataturk's first name was Kemal/Kamal. Of course, that's what I get for only knowing his name from the Monty Python fish license sketch.
Seems he was given the name Mustafa at birth and was given or acquired the name Kemal later and dropped the name Mustafa. So Kemal should be accepted as that's the name he went by.
The first Palin I think of is always Michael Palin. I know he isn't a political figure, but trying his name did get me one of the other answers in this quiz. :)
I don't think there's any dilemma in this particular case
I guess only we WWII geeks know Tojo's first name.