In 1649, the Irish, led by Donald Macalister Mullach, attacked Thurso and were chased off by the residents, headed by Sir James Sinclair. One of the locals, a servant of Sinclair was said to have killed Mullach by "cutting a button from his master's coat and firing it from a musket". In 1811, the parish had 592 houses with a population of 3462. This had decreased to 2,510 people by 1841. Following the passage into law of the 1845 Poor Law Act, a combination poorhouse was constructed; work commenced in 1854 and was completed by 1856. The building, which had a capacity to house 149 inmates, was on a site to the west of Thurso Road and provided poor relief for Thurso and the parishes of Bower, Canisbay, Dunnet, Halkirk, Olrig, Reay and Watten. Many of the poorhouses in Scotland were under used, and by 1924 the building had been unoccupied for several years so was sold; it was later utilised as housing but by 2001 was again abandoned.