The Battle of George Square was a violent confrontation in Glasgow, Scotland between City of Glasgow Police and striking workers, centred around George Square. The "battle", also known as "Bloody Friday" or "Black Friday", took place on Friday 31 January 1919, shortly after the end of the First World War. During the riot, the Sheriff of Lanarkshire called for military aid, and government troops, supported by six tanks, were moved to key points in the city. The strike leaders were arrested for inciting the riot. Although it is often stated that there were no fatalities, one police constable died several months later from injuries received during the rioting.

Glasgow is the most populous city in Scotland, the third-most populous city in the United Kingdom, and the 27th-most populous city in Europe. In 2022, it had an estimated population as a defined locality of 632,350 and anchored an urban settlement of 1,028,220. Glasgow became a county in 1893, the city having previously been in the historic county of Lanarkshire, and later growing to also include settlements that were once part of Renfrewshire and Dunbartonshire. It now forms the Glasgow City Council area, one of the 32 council areas of Scotland, and is administered by Glasgow City Council.