Montebello (Italian for beautiful mountain) is a city in Los Angeles County, California, United States, located in the southwestern area of the San Gabriel Valley on 8.4 sq mi (22 km2) 8 mi (13 km) east of downtown Los Angeles. It is considered part of the Gateway Cities, and is a member of the Gateway Cities Council of Governments. In the early 20th century, Montebello was a well-known source for oil reserves. At the 2010 census, the population was 62,500. The estimated population as of July 1, 2019 was 61,954.
Before the arrival of the Spaniards in the area known today as Montebello, the land along the Rio Hondo River was populated by the Tongva (Gabrielino) portion of the Uto-Aztecan family of Native Americans. The Tongva occupied much of the Los Angeles basin and the southern Channel Islands - Santa Catalina, San Nicolas, San Clemente and Santa Barbara; when Spanish explorer Juan Rodrigues Cabrillo arrived off the shores of Santa Catalina in 1542, he was met by the Tongva people. Because the language of the Tongva was different from the neighboring tribes it was called "Gabrielino" by the Spanish. As more non-natives arrived and settlements were established, illness and disease came with them. By 1870, the area had few remaining indigenous inhabitants as disease brought by the Europeans killed many of the Tongva.
Father Angel Somera and Father Pedro Cambon, both Franciscan missionaries, founded the original Mission San Gabriel Arcangel, called Mission Vieja on September 8, 1771; the location is today near the intersection of San Gabriel Boulevard and the Rio Hondo River. The establishment of the mission marked the beginning of the Los Angeles region's settlement by Spaniards and the fourth of twenty-one missions ultimately established along California's El Camino Real.