This may refer to the Scottish Insurrection of 1820, or the ‘Radical War’ which was centred on the city of Glasgow. Radical demands for reform led to a call for strike action in early April and small groups of people began to march in protest in and around the city and its factories. Government troops put down the demonstration and three leaders were hanged; a further twenty sentenced to deportation. It was evident that the unrest had been activated by the government through the dissemination of rumours, as a ploy to bring the Radical leaders into the open and publicise the dangers of radicalism. After this, the sentiment died down and the event was largely forgotten.
View a short clip from the BBC about the Radical War.