Katherine Schlater [Schleter], painter, illustrator, printmaker, designer, and teacher, was born in Philadelphia, Pennsylvania on 10 October 1893 to Frank J. and Mary Schlater (Schleter). She studied at the Philadelphia Museum School of Industrial Art; and with Hugh Breckenridge and Ralph M. Pearson and Earl Horter. In the 1940 census, Schlater is listed as living on Fillmore Street in Philadelphia with her widowed mother.  Her occupation is listed as a teacher with two years of college education.

Schlater was a member of the Philadelphia Artists Alliance, the Philadelphia Print Club, the American Artists Professional League, and The Plastic Club. Her work was included in the Pennsylvania Academy of the Fine Arts annual 1943-44, and in 1961, she was included in the West Comes East exhibition at the Newman Galleries in Philadelphia organized by Morris Blackburn. As a designer, she created fabric designs for the Celanese Corporation of America.

At some point after the death of her mother in 1946, Schlater moved to Santa Fe, New Mexico where she taught privately. In 1950, she is listed as living at 1000 Camino Rancheros in Santa Fe. On 27 March 1955, she sailed to Greece on the ship Queen Frederica and the ship's log records that she planned a six month stay.  

As a printmaker, Schlater created block prints and lithographs and she embraced surrealism in her drawings. As a painter, she created murals in private homes.

Katherine Schlater died in Santa Fe, New Mexico on 12 August 1982.