The Mask of Anarchy, as its subtitle announces, was “Written on the Occasion of the Massacre at Manchester” in St. Peter's Field on 16 August 1819. The event, popularly known as the Peterloo Massacre, occurred when mounted local militia mistakenly charged a crowd of men, women, and children, who were peaceably campaigning for Parliamentary reform, and incited a riot. A number of people lost their lives and a good many more were seriously injured as a result of the violence that ensued. Having taken up residence in Italy by this time, Shelley did not learn of this terrible event until he received copies of the Examiner for 22 and 29 of August from Thomas Love Peacock (1785-1866) on 5 September. Shelley's response t…
Sandy, Mark. "The Mask of Anarchy". The Literary Encyclopedia. First published 20 September 2002; last revised 30 November -1.
[http://www.litencyc.com/php/sworks.php?rec=true&UID=213, accessed 27 April 2015.]