For other incidents referred to by this name, see Bloody Sunday.

Bloody Sunday, London, 13 November, 1887 was a demonstration against coercion in Ireland and to demand the release from prison of MP William O'Brien. The demonstration was organised by the Radical Federation .

Some 10,000 marchers approached Trafalgar Square from several different directions, led by (among others) John Burns, Annie Besant and Robert Cunninghame-Graham, who were primarily leaders of the S.D.F (Social Democratic Federation).

Two thousand police and 400 troops were deployed to halt the demonstration but in the ensuing clashes many people were so badly beaten they required hospital treatment; Burns and Cunninghame-Graham were arrested and imprisoned for six weeks.

These tactics brought excellent publicity for the S.D.F but achieved little else, since as there were better economic conditions and the Irish Issue was curtailed later in the year as well as the beginning of 1888, the agitation died away.