Belfast is situated on the north-east coast of Ireland at the mouth of the River Lagan. The town grew up around a Norman castle built in 1178. Partly destroyed in the sieges of the Civil War, Belfast was rebuilt and during the 17th century the arrival of refugee Huguenot weavers helped the city's textile trade. By the 18th century became Ireland's principal manufacturing centre. Belfast's growing prosperity helped to increase the population from 8,500 in 1750 to 20,000 by 1800.

The main trade in Belfast was cotton and linen but after 1850 shipbuilding became very important. The growth-rate in Belfast in the second-half of the 19th century was the greatest in the British Isles and by 1900 the population of the city was 350,000.