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. Robertson was best known as an advocate of the Christ myth theory. He wrote in February 1906 to a friend that he gave up the ‘divine’ when he was a teenager. It was through the Edinburgh Secular Society that he met William Archer and became writer for the Edinburgh Evening News. He eventually moved to London to become assistant editor of Bradlaugh’s paper National Reformer, subsequently taking over as editor on Bradlaugh’s death in 1891. Robertson was also an appointed lecturer for the freethinking South Place Ethical Society from 1899 until the 1920s.