John Mackinnon Robertson PC (14 November 1856 - 5 January 1933) was a prolific journalist, advocate of rationalism and secularism, and Liberal Member of Parliament in the United Kingdom for Tyneside from 1906 to 1918. He was an advocate of the Jesus-Myth theory, and in several books he argued against the historicity of Jesus. According to Robertson, the character of Jesus in the New Testament developed from a Jewish cult of Joshua, whom he identifies as a solar deity.