Ralph Mosher Pearson was born on May 27, 1883 in Angus, Iowa.  He studied at the Art Institute of Chicago with C. F. Browne and John Vanderpoel. In 1913, at the New York Armory, the American public was invited to see for the first time a large-scale exhibition of the work of the modern movement. Pearson traveled from Chicago for what was to prove to be for him a change of direction and an enlargement of vision. In 1914, he found 'the first school of modern art in this country, taught by Hugo Robus,' and where he was to 'inaugurate a painful unlearning and relearning process of some eight years' duration which was a cheap enough price to pay for a basic reorientation.'

Pearson moved to northern New Mexico in the 1920s. He also spent time in California, exhibiting at the Stendahl Gallery in Los Angeles in 1923. He settled in East Gloucester, Massachusetts and finally in Nyack, New York. Pearson was a full member of the Art Students League of Chicago, the Chicago Society of Etchers, the New York Society of Etchers, California Art Club, the California Society of Etchers and the Brooklyn Society of Etchers. Ralph M. Pearson died in South Nyack, New York on April 27, 1958.