In the republics of ancient Greece and Rome, during the whole period of their existence, and under the feudal governments, for a considerable time after their first establishment, the trade of a soldier was not a separate, distinct trade, which constituted the sole or principal occupation of a particular class of citizens; every subject of the state, whatever might be the ordinary trade or occupation by which he gained his livelihood, considered himself, upon all ordinary occasions, as fit likewise to exercise the trade of a soldier, and, upon many extraordinary occasions, as bound to exercise it.