During the period in which the populares party controlled the city, they flouted convention by re-electing Marius consul several times without observing the customary ten-year interval between offices. They also transgressed the established oligarchy by advancing unelected individuals to magisterial office, and by substituting magisterial edicts for popular legislation. <answer>Sulla</answer> soon made peace with Mithridates. In 83 BC, he returned to Rome, overcame all resistance, and recaptured the city. <answer>Sulla</answer> and his supporters then slaughtered most of Marius' supporters. <answer>Sulla</answer>, having observed the violent results of radical popular reforms, was naturally conservative. As such, he sought to strengthen the aristocracy, and by extension the senate. <answer>Sulla</answer> made himself dictator, passed a series of constitutional reforms, resigned the dictatorship, and served one last term as consul. He died in 78 BC.
Which leader had achieved peace with Mithridates?
Sulla