The Santa Ysabel Asistencia was founded on September 20, 1818 at Cañada de Santa Ysabel in the mountains east of San Diego (near the village of Elcuanan), as a asistencia or "sub-mission" to Mission San Diego de Alcalá, and to serve as a rest stop for those travelling between San Diego and Sonora. The native population of approximately 450 neophytes consisted of both Luiseño and Diegueño peoples. Based on historical records, Santa Ysabel enjoyed a higher-than-average conversion rate when compared to the other California missions. Given its remote location, the facility was visited infrequently by the padres after secularization of the missions in the 1830s. History Mission era (1769–1833) Father Juan Mariner first visited the site in 1795. In 1816, mission fathers in San Diego formally requested permission from the Spanish Governor to establish the asistencia. Fray Martin presided over the inaugural mass on the last day of September 1818. By 1821, a chapel, granary, several adobe houses, and a cemetery had all been constructed on the site. In September of that same year Father Mariano Payeras, "Comisario Prefecto" of the California Missions, visited the area as part of a plan to establish an entire chain of inland missions, with Santa Ysabel as the "mother" mission. The plan never came to fruition, however. Rancho era (1834–1849) The missions were secularized in 1834, and Jose Joaquin Ortega and Edward Stokes received the Rancho Santa Ysabel Mexican land grant in 1844. A wagon road to Warner's Ranch from San Diego passed through the site from this time. In 1846, General Stephen W. Kearny and the "Army of the West" made camp on the rancho on their way to the Battle of San Pasqual following this road. Jean Baptiste Charbonneau, son of Sacagawea, camped at the Mission in 1847 after guiding the Mormon Battalion from New Mexico to San Diego. In 1849, U.S. Army Lieutenant A.W. Whipple visited the site during the course of the United States and Mexican Boundary Survey and documented the Mission's condition as being "in ruins." California statehood (1850–1900) In 1850, the roof caved in and shelters were erected against one wall in order to allow religious services could continue. John Russell Bartlett, an American traveller who passed by the Mission proper in 1852, noted that the facility consisted of little more than a roofless church and a few simple huts; nothing remains of the original structures due to