The Conflict of the Orders, also referred to as the Struggle of the Orders, was a political struggle between the Plebeians (commoners) and Patricians (aristocrats) of the ancient Roman Republic lasting from 494 BC to 287 BC, in which the Plebeians sought political equality with the Patricians. It played a major role in the development of the Constitution of the Roman Republic. Shortly after the founding of the Republic, this conflict led to a secession from Rome by Plebeians to the Sacred Mount at a time of war. The result of this first secession was the creation of the office of Plebeian Tribune, and with it the first acquisition of real power by the Plebeians.
At first only Patricians were allowed to stand for election to political office, but over time these laws were revoked, and eventually all offices were opened to the Plebeians. Since most individuals who were elected to political office were given membership in the Roman Senate, this development helped to transform the senate from a body of Patricians into a body of Plebeian and Patrician aristocrats. This development occurred at the same time that the Plebeian legislative assembly, the Plebeian Council, was acquiring additional power. At first, its acts ("plebiscites") applied only to Plebeians, although after 339 BC, with the institution of laws by the first Plebeian dictator Q. Publilius Philo, these acts began to apply to both Plebeians and Patricians, with a senatorial veto of all measures approved by the council.
It was not until 287 BC that the Patrician senators lost their last check over the Plebeian Council. However, the Patricio-Plebeian aristocracy in the senate still retained other means by which to control the Plebeian Council, in particular the closeness between the Plebeian Tribunes and the senators. While this conflict would end in 287 BC with the Plebeians having acquired political equality with the Patricians, the plight of the average Plebeian had not changed. A small number of aristocratic Plebeian families had emerged, and most Plebeian politicians came from one of these families.
In 494 BC Rome was at war with three Italic tribes (the Aequi, Sabines and Volsci), but the Plebeian soldiers advised by Lucius Sicinius Vellutus refused to march against the enemy, and instead seceded to the Sacred Mount outside Rome. A settlement was negotiated and the patricians agreed that the plebs be given the right to elect their own officials. The Plebeians named these new officials Plebeian Tribunes (tribuni plebis).