The first Welsh asylum for the mentally ill was opened in Swansea at May Hill in 1815, followed in 1844 by Vernon House in Briton Ferry. The Glamorgan County Asylum in Bridgend opened twenty years later to serve the whole of the county of Glamorgan. But with the 1891 Public Health Act required each County Borough to build its own asylum .

This took a long time to implement, for initially Townhill was thought to be the place to build an asylum, until in 1908 the Cefn Coed site was considered. Nearly 250 mentally ill persons from the Swansea area were being treated elsewhere.

Eventually land was purchased, and the foundations were nearly complete when during the First World War shortage of labour and materials caused a halt. Building work began in 1928, utilising Unemployment Relief schemes, as with the erection of the Guildhall and Tir John Power Station. The Swansea Mental Hospital was opened in December 1932 by the Princess Royal (the daughter of King George V).