Prior to 1834, each parish had responsibility for looking after its own poor, which was a great drain on parish resources, and was, too often, managed inadequately. The Poor Law Amendment Act of 1837 made provision for parishes to join together in a 'Union' and thus Union workhouses came into being. The Boston Union of 28 parishes was formed in 1836 and commissioned the building of St John's workhouse in Skirbeck Road to house 350 paupers in 1837.
The building was extended several times before workhouses were abolished in 1929 when it became an old people's home. It also served other functions, including HMS Arbella (for the Navy during the war), as a boy's school, a weights and measures office and a Civil Defence headquarters. Its final closure came in the1970s and most of the buildings were demolished in 1978 leaving Scott's grand gatehouse. This steadily fell into ruin until Heritage Lincolnshire restored and repaired the structure in 2001. The building, renamed Scott House is now owned by Lincolnshire County Council and operates as a resource centre for adults with physical disabilities.