A Roman settlement in conquered territory, a name first used in the later Republican and imperial Roman periods to a township, often of retired veteran soldiers, strategically placed to defend imperial interests. Its self-governing constitution imitated that of Rome, and the citizens had either full (Roman) citizenship or limited (Latin) citizenship. After the 2nd century BC, colonia became the highest rank that a community could attain. It involved a transfer of Roman citizens to a settlement in order to administer it in collaboration with the magistrates of the capital. In exchange for a commitment to provide military aid, its citizens acquired the right to trade and contract marriages with Roman citizens. In the Greek world, a colony was a city founded by a contingent of Greek citizens in a foreign territory for agricultural and/or commercial purposes.