These cities could vary enormously both in population and territory from the tiny Greek poleis of several hundred citizens to the great metropoleis such as Alexandria or Antioch.
Despite these differences, these cities shared certain governmental structures and were free, in varying degrees depending on the community’s status, to manage their own affairs.
During the civil discord of the late Republic and Second Triumvirate, colonies were founded on the whim of dynasts such as Sulla and Julius Caesar without such a law.
Beginning in 118 BC in Gallia Narbonensis, colonies began to be established in Rome's provinces, and from this point onwards coloniae were especially used for settling demobilized soldiers and in programs of agrarian reform.
Following the Social War, Roman citizenship was awarded to all Italy, with the result that a municipium was effectively now a community of citizens.