The prevailing view in Scottish historical thinking is that the Catholic Irish in Scotland during the first half of the nineteenth century did not participate in strikes, trade unions or political movements with Scottish workers. This, it has been argued, was because they were despised by the Scots because of their race and religion and because they were employed mainly as strike-breakers or low wage labour. As a result the Catholic Irish formed a separate community in Scotland and were concerned mostly with issues concerning Catholics, the Catholic Church and Ireland. This thesis is concerned with the Irish in the west of Scotland during the period from c.1797 to 1848. It discusses the role of the Catholic Irish in the campaigns for Catholic Emancipation and repeal of the British-Irish Act of Union and demonstrates that their involvement in these agitations occurred despite the objections of the Scottish Catholic clergy. The thesis examines the various movements in the region for political reform and provides evidence of Irish, including Catholic Irish, involvement. Scottish reformers welcomed this Irish participation. Moreover, when the bulk of the Catholic Irish in Glasgow, and probably elsewhere in the region, eschewed involvement in Chartism between 1838 and 1842 the chartists tried in vain to persuade them to participate. The Irish Repeaters in Glasgow chose instead to campaign for the Six Points along with the Complete Suffragists. In 1848 the Repeaters and chartists in the west of Scotland finally formed an alliance. The thesis also investigates the issue of the Irish and industrial action in the region and shows that although some Irish workers were strike-breakers and low wage labour, others, most notably in cotton spinning, weaving and mining, were involved in strikes and trade unions to protect and improve their economic condition.