Location: Orange County, California

Name is derived from Santiago Creek, a tributary of the Santa Ana River which was named by the first Portoli Expedition (1769) after the Apostle Saint James the Greater (d.44), the only Apostle whose martyrdom is recorded in the New Testament, and who is the Patron Saint of Spain. July 25 is his Feast Day.

There was also a 78,941 acre (Spanish) Rancho Santiago de Santa Ana (1810). The creek has its source in what was first called the Santa Ana Mts in the Surveyor General's Map of Public Surveys in California (1855).

GLO Surveyor Henry Hancock first cited a "Santiago Cañon" (1855).

At an indeterminate time, the creek and canyon names were extended to these mountains which then came to be known as the Sierra de Santiago. This peak is the highest point, so its summit came to be distinguished as the Santiago Mountain. Dr. Stephen Powers noted in the 10th Report of the State Minerologist (1890) that "The highest point of land is what is known as Saddleback or Santa Ana Peak. In the early days it was known as Santiago Peak. The USGS, while mapping the Corona quadrangle, also called it by this name (1899)-and this name stuck.

The Juaneño Indians had originally called it Kalawpa and considered it a sacred mountain and an abode of their supreme god Chiningchinish.

To the padres of Mission San Juan Capistrano (1776) it was known as part of the twin domed Cerro del Trabuco. The range was known as the Sierra del Trabuco-tradition has it that a Spanish soldier lost his blunderbuss firearm in a camp located in what would later be known as Trabuco Canyon.

Other variant names for this peak are Trabuco Peak, Old Saddleback, Cold Water Peak, Mount Downey, Sierra San Juan, Santiago Mountain, Santa Ana Peak and Temescal Peak.

First trail up the summit was constructed by Andrew Joplin (1890), the USFS built a fire road (1926), and later the CCC improved the Holy Jim and Coldwater Canyon Trails to the top (ca.1933). The USFS constructed an H-B type fire lookout on the summit (1934), rebuilt (1951) consisting of a 35' open steel h-brace tower topped by a CIO type 13' by 13' metal cab.

This is the high point of the Santa Ana Mountains.

Name first appears on the State Mining Bureau Preliminary Map of California (1891).

Name officially accepted by USBGN (1961).

Peak was on the original 1946 HPS Peak List. Weldon Heald climbed this peak in 1933.