The primary requisites, in my opinion, of a good DBA, are reasonable intelligence, a reasonable level of dedication, a high level of integrity, and an amazing tollerance for boredom.

Alexander the Great would have been a horrible DBA, simply due to the lack of tollerance for boredom, if nothing else.

Machiavelli would probably have been bad at it too, though more through a rejection of the necessity for integrity.

Archimedes might have made a good DBA, but he'd have to have been on the cutting edge of some challenging technology to keep him interested. The "please don't disturb my circles" thing shows a good ability to keep cool while under pressure, but also a tendency to mis-assign priorities in an emergency.

Sun Tzu would more likely take Codd's place than be a simple DBA. Same might be said for Archimedes, of course.

Pythagoras would be a bit too eccentric to get through most job interviews, but if he couldn't find an employer, he'd have created his own database engine and might be a mover-and-shaker in the open source scene.

Nobody would understand Nikolai Tesla's database designs, but they would totally rock. That might work out, might not. (Generations after he died, mere geniuses would be saying things like, "Oh! I finally understand why he built that index that way!")

Albert Einstein would know more about relational theory and the internal workings of the engine than anyone, but would forget to set up maintenance plans and verify backups. The next generation of databases would benefit tremendously from his theories.

Robert Oppenheimer would build gargantuan databases with unbelievable performance, but would lose his access to them through political manipulation.

Yeah, this is kind of fun.