Watterson was called "the last of the great personal journalists", writing colorful and controversial editorials on many topics under the pen name "Marse Henry". Hundreds of American papers republished them; they were an early exemplar of the syndicated column which played a significant role creating public support for U.S. intervention in the First World War. Watterson won the Pulitzer Prize in 1918 for two editorials supporting U.S. entry into World War I ("" and ""), and he remained the paper's editor until 1919, retiring after conflicts with Robert Worth Bingham, who purchased the paper in 1918.