15 Cornelius Sulla.

http://www.sjsu.edu/faculty/watkins/caesarjulius.htm

One leader prior to Caesar arose that gained the power to make such reforms. His name was Lucius Cornelius Sulla.

Lucius Cornelius Sulla was born in 138 BCE into a patrician family of Rome, but one with little power and influence. He aspired to a political career but he had little success until 78 BCE when he became quaestor (financial officer) in an army commanded by Gaius Marius. 

The Senate authorized Marius to go to North Africa to wage ware against the local leader Jugurtha. Jugurtha was a Berber leader that had a turbulent relationship with Rome. Jugurtha was the illegitimate son of a former king of Numidia, which roughly corresponded to what is now Algeria.