Richard Arthur Rigg (January 5, 1872 – August 1, 1964) was a Methodist minister and politician in Manitoba, Canada. He served in the Legislative Assembly of Manitoba from 1915 to 1917, and is notable as the first member of the Social Democratic Party to serve in that body. Rigg was born in Todmorden, Lancashire, England, and came to Canada in 1903. He was a bookbinder as well as a Methodist minister, and served as a first permanent business agent of the Winnipeg Trades Council. He was initially a member of the Socialist Party of Canada, but broke away from the SPC in 1911 to help form the Social Democratic Party. Along with Jacob Penner and Herman Saltzman, he co-authored the SDP's first manifesto. By 1917 he had a wife and five children. Rigg campaigned for the House of Commons of Canada in the 1911 federal election, but finished third in the riding of Winnipeg against Conservative Alexander Haggart. In 1913, Rigg was elected to the Winnipeg City Council for Ward Five in the city's north end. He received considerable support from the city's Jewish community, and in his victory speech pledged to support religious, national and political equality for all members of Canada's working class. Rigg's victory began a tradition of social-democratic representation in Winnipeg's council which has continued to the present day. Rigg was elected to the Manitoba legislature in the provincial election of 1915, defeating Liberal candidate Solomon Hart Green by 231 votes in the Winnipeg North "B" constituency. Nominated as an SDP candidate, Rigg also received support from the more centrist Labour Representation Committee. During the 1915 campaign, Rigg and fellow SDP candidate Arthur Beech emphasized both general reforms and the broader working-class struggle. Their meetings were often disrupted by members of the more hardline Socialist Party, who accused Rigg and Beech of being "sentimentalists and Christ-lovers". The Socialists did not field candidates against them, however, and could not prevent Rigg's victory. Rigg's success was credited, in part, to a strong support base among ethnic communities in Winnipeg's north end. In the legislature, Rigg pressed for improvements to Manitoba's Factories Act, and unsuccessfully attempted to raise the minimum age of factory labour. Rigg was generally supportive of the provincial Liberal government of Tobias Norris, claiming that the Norris administration did more for labour in its first six months than the previous Conservative administration of Rodmond Roblin had