Red Clydeside is the era of political radicalism that characterised the city of Glasgow in Scotland, and urban areas around the city on the banks of the River Clyde such as Clydebank, Greenock and Paisley. The history of Red Clydeside is a significant part of the history of the labour movement in Britain as a whole, and in Scotland in particular.
This period in Clydeside's history lasted from the 1910s until roughly the early 1930s, although its legacy is still visible today. Popular newspapers of the time used the term "Red Clydeside" to refer to the political militancy of the time. An amalgamation of charismatic individuals, organised movements and socio-political forces led to the enduring notion of Red Clydeside. This period has its roots directly in working class opposition to Britain's participation in World War I, although the area had a long history of political radicalism going back to its involvement in the Friends of the People society and the "Radical War" of 1820.
The 11,000 workers at the largest Singer sewing machines factory, in Clydebank, went on strike in March–April 1911, ceasing to work in solidarity with 12 female colleagues protesting against work process reorganisation. This reorganisation involved an increase in workload and a decrease in wages. Following the end of the strike, Singer fired 400 workers, including all strike leaders and purported members of the IWGB, among them Arthur McManus, who later went on to become the first chairman of the CPGB between 1920 and 1922.