Katherine "Kate" S. Peirce (b. Switzer) (1853-1936) was born in Brooklyn, New York, and died in Summit, New Jersey. In 1873 she married William C. Peirce. He was a stockbroker who later became a partner in the firm Peirce & Williams, a woodworking and lumber dealership, and finally worked for a tanning mill. By 1880 they were living in Philadelphia, Pennsylvania, and by the mid-1880s they had moved to Bristol, Pennsylvania, where they remained until at least 1910. Thereafter they moved to Langhorne, Pennsylvania. Sometime after her husband's death in 1921, Peirce moved to Summit. She studied Christian Science with Mary Baker Eddy's student J. Allen Campbell then took Eddy's Primary class in August 1886. Thereafter she joined the Christian Scientist Association but withdrew in 1888, citing inability to attend due to distance.

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