Older names for the settlement were 'Colume' and 'Coleham', and the Domesday Book lists the manor as 'Colnun'. Cowlam in 1066 was in the Hundred of Toreshou, of eighteen geld units—taxable units assessed by hide area—and contained 5.6 households and three ploughlands. In 1066 the lordship was held by Ketilbert, who held thirteen manors in the north of Yorkshire. Cowlam was transferred in 1086 directly to king William I.[1][2]
Cowlam was previously a Bronze Ageencampment, evidenced by earthworks, 0.5 miles (0.8 km) from the hamlet, and a later medieval village that was deserted in the late 17th century.[1][3]
In 1931 the civil parish had a population of 47.[4] On 1 April 1935 the parish was abolished and merged with Cottam.[5]