Cicero was a Roman statesman and orator. He lived from 106 to 43 BCE.
Cicero, then, was alive at the time when the Roman Republic was crumbling and about to turn into the Roman Empire. Cicero was most important for the fact that he tried to analyze and put a halt to the problems that were plaguing the Republic. Cicero wanted to return to a system of the "concord of the orders" in Rome. He wanted to end the sort of class warfare that led to such things as the attempted coup headed by Catiline.
However, Cicero was not able to make this happen. Rome moved towards an imperial system and Cicero was killed because of his outspoken opposition to this change.