Rome was a Republic for about 500 years
After defeating Tarquin, the last king of Rome, Rome was a republic. The republic lasted almost 500 years.
The Roman Republic was run by the Senate, which was made up of members of the patricians (the rich). The people of Rome elected the two top Senators called consuls. The consuls selected senators. You could only be a consul for one year, then you had to be elected by the people again. This system worked well. The Republic lasted almost 500 years. Compare that to the USA, which is only about 250 years old, and you get an idea of how successful they were.