Colonial troops or colonial army refers to various military units recruited from, or used as garrison troops in, colonial territories.
Such colonies may lie overseas or in areas dominated by neighbouring land powers such as China or Russia. Colonial troops have been used by Imperial powers whether ancient (such as Carthage and Rome), or modern (such as Great Britain, France, Netherlands, Denmark, the United States, Germany, Italy, Spain, and Portugal). Sometimes they have been recruited under local leaders, as auxiliaries, at other times directly under pay and officers from the colonial power. They must in turn be seen as part of larger systems of power projection, which may also contain chains of overseas bases and refuelling stations, ships, aircraft, alliance systems and fiscal strength.
At the beginning of the modern colonial period such troops were predominantly Europeans from the home army of the country concerned, but locally raised "native" troops were soon recruited. The latter normally served in separate units, at first under their own leaders, later under European officers.
The sepoys of the English and later British East India Company were an early example. By the mid 18th century, these troops were beginning to be directly recruited by the Company, allowing more systematic provisioning, drill and tactics. During the Indian Rebellion of 1857, or "Sepoy Mutiny", many of the sepoys rebelled against the Company, leading to the end of Company rule in India. After the British government took direct control of British India in 1858, the sepoys formed the regiments of the Indian Army, some of which survive to the present day in the national armies of Pakistan and India.
The French and Portuguese enclaves in the Indian subcontinent also recruited sepoys.