Rome became the ruler of a great Mediterranean empire. The new provinces brought wealth to Italy, and fortunes were made through mineral concessions and enormous slave run estates. Slaves were imported to Italy and wealthy landowners soon began to buy up and displace the original peasant farmers. By the late 2nd century this led to renewed conflict between the rich and poor and demands from the latter for reform of the constitution. The background of social unease and the inability of the traditional republican constitutions to adapt to the needs of the growing empire led to the rise of a series of over-mighty generals, championing the cause of either the rich or the poor, in the last century BCE.