The Torrance area's original inhabitants were the Tongva Indians, who lived in reed-covered houses made of willow poles. These original people made canoes from logs, built reed boats and fished along the coast in summer, moving inland to hunt in winter.

Portuguese explorer Juan Rodriguez Cabrillo was the first European to visit the area, arriving in 1542. After that, the Spanish traded with the Tongva people from time to time and sometimes anchored their ships along the shore.

In 1784, Juan Jose Dominguez, a member of the 1769 Portola Expedition received a 75,000-acre Spanish land grant called Rancho San Pedro, the first Spanish land grant in Alta California. The Dominguez family held this land until 1912, when Jared Sidney Torrance bought 2,791 acres of land from the Dominguez Estate Company.

Torrance envisioned a planned, industrial town of 500 people, fully built with paved streets, sewer and water lines underground and landscaped before anyone came to live in it, and jobs would be waiting for them when they arrived. The first businesses to establish themselves here were the Union Tool Company (a branch of the Union Oil Company), Llewellyn Iron Works, and Pacific Electric.

Prominent Boston architect Frederick Law Olmstead, Jr. was engaged to lay out the new city, with commercial and industrial zones located on the east side of town, so the prevailing westerly winds would blow factory smoke away from the residential areas.

Torrance's first oil well was dug in December, 1921. It was a gusher, and within six months, the city's population of 1,800 swelled to 2,750. By 1925, 582 wells were producing oil in Torrance. Production declined in the late 1950s, and by the early 1960s, all the old wooden oil derricks were gone.

Rapid growth in the Torrance area began after World War II as wartime industries were transformed into aerospace and related industries. Large housing developments were built in the 1950s and 1960s to accommodate the new population.