Macroom began as a meeting place for the Druids of Munster. It is first mentioned is in 6th-century records, and the immediate area hosted a major battle c. 987 involving the Irish king Brian Boru. During the middle ages, the town was invaded by a succession of warring clans, including the Murcheatach Uí Briain and Richard de Cogan families. In the early modern period the MacCarthy's took control and later the area found prosperity via milling. The MacCarthys built a series of tower houses, many of which survive. The family lost influence during the Williamite wars of the 1690s, after which authority over the town castle waxed and waned between the MacCarthys and a number of ambitious English families. In the 17th century, Macroom became a central point of conflict in the Cromwellian conquest of Ireland.