The Free Church of Scotland's home-mission campaign played a major role in the Church's attempt to define itself as the true national Church of Scotland following the Disruption of the Church of Scotland in 1843. It also represented the Free Church's effort to confront the problems of irreligion and social degradation which accompanied industrialisation and urbanisation. The study begins with the contribution of Thomas Chalmers (1780-1847). As a Church of Scotland minister in Glasgow between 1815 and 1823, Chalmers endeavoured to make the parish the focal point for the local community. Chalmers was supported in his ministry by a large voluntary agency which visited local residents and encouraged self-help and communal responsibility. He created a system of day and Sunday schools, and sought to reform the system of poor relief. The aim was to create self-reliant district communities, through what was termed the 'territorial plan'. This thesis argues that Chalmers' posthumous contribution to home-mission work, through his writings on the territorial plan and missionary work in Glasgow and Edinburgh, profoundly influenced the social outreach of all the Presbyterian Churches, and especially the Free Church, in nineteenth-century Scotland. Territorialism gave the Presbyterian Churches a valuable link to those groups in society which had been adversely affected by urbanisation and industrialisation. The thesis also considers how the home-mission movement in Scotland was influenced by external forces such as political, social and economic developments as well as religious matters such as theological controversies, Church union negotiations and a growing disestablishment campaign. This thesis demonstrates how the Free Church's territorial campaign was a fundamental aspect of its commitment to an essentially new, predominantly urban society.