For the letter U, you might try various Praetors (magistrates) who were styled Praetor Urbanus, or research the office itself. The word urban speaks for itself. Some of them rose to high position and great influence. Praetor Urbanus was a very early magisterial office of the ancient republic.
Also, there was an early 3rd century Pope, Pope Urban. He reigned 222-30 A.D. Not much known about him, so might be worth some brownie points investigating.
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Life is just a bowl of cherries, and that makes for an awful lot of stones.