David Daniel Irving (31 October 1854 – 25 January 1924) was a British socialist activist and Labour Party Member of Parliament.
After he lost his leg in an industrial accident, the Midland Railway forced him to take a pay cut.
Instead, he became a socialist lecturer, and then in 1894, secretary of the Burnley branch of the Social Democratic Federation (SDF).
In the 1906 general election, SDF leader H. M. Hyndman stood in the Burnley constituency, and came within 350 votes of winning the seat.
In 1914, he was a supporter of British action in World War I, and as a result, when the SDF split on the issue, he joined Hyndman's new group, the National Socialist Party.