Juan Crespi (hwän krās´pē), 1721–82, Spanish explorer in the Southwest, a Franciscan. He came to America in 1749, and in 1767 he went to the peninsula of California in charge of Mission Purísima Concepción. In 1769 he joined the expedition of Gaspar de Portolá to occupy San Diego and Monterey and continued up the coast with Portolá. The following year he founded the Mission San Carlos Borromeo, in the present-day Carmel-by-the-Sea, which became his headquarters. He was chaplain of the expedition to the N Pacific conducted by Juan Pérez in 1774. His diaries, published in H. E. Bolton's Fray Juan Crespi (1927, repr. 1971), provided valuable records of these expeditions.