What was the setup of the Romans republic?

Answer 1

The Roman senate was originally established by Romulus (Rome's founder and first king) when he founded Rome. He selected 100 pater familias (fathers of the family/heads of the household) form the leading clans of Rome of the time to sit in a council of elders (senate comes from the word senex which means old man). This was the advisory body of the king.

In the Republican period the senate continued to be an advisory body. During the Early Republic the patricians (the descendants of the original pater familias) monopolised the seats of the senate. Later, the rich plebeians were co-opted into a patrician-plebeian oligarchy and gained access to the senate. At this point the senate was composed of former senior officers of state and of people enrolled by the censor, an officer of state who kept the roll of senators and could appoint new senators or expel current senators. His decisions were based on appropriate stats, merit, and a code of conduct. Later still, Lucius Cornelius Sulla doubled the size of the senate, made former junior officer of state eligible for a seat in the senate and increased their numbers, so that all senators were former officers of state.