Missionary in Pimería Alta; b. Lucerne, Switzerland, Sept. 1, 1687; d. Ures, Mexico, Sept. 28, 1761. The third of 17 children of Heinrich Ludwig Segesser and Maria Katharine Ruscone, he entered the Society of Jesus at Landsberg, Bavaria, in 1708, studied theology at Jesuit University of Ingolstadt (1719–22), and was ordained in 1721. In 1731 he arrived in New Spain (Mexico), with several other Jesuits from the Germanies. (After 1675, Spain had allowed non-Spanish missionaries into her Indies.) In that same year he was sent north to the Pimería Alta mission, then in a period of revival and expansion. After Segesser had studied the Indian languages at San Ignacio, the elder Capt. Juan Bautista de Anza, father of a more famous son, took him to the outpost station, earlier served by kino, where the San Javier del Bac mission (near the modern Tucson) was formally established. Later he was in charge at Guévavi, and for a time was superior in the Pimería. During this time Segesser wrote a very valuable and penetrating account, Una relación, describing life on that far frontier. He, Keller, Sedelmayr, Stiger, and others were the great figures there in the mid-18th century.
Bibliography: p. segesser, "The Relation of Philipp Segesser," ed. and tr. t. treutlein, Mid-America 27 (1945) 139–187, 257–260.
[j. f. bannon]