Butte County was historically a bountiful area covered with oak trees, fields of manzanita brush, and marshes and lakes in the rainy season.

The valley floor abounded with wild game, geese and ducks overhead, deer, antelope, tule elk, the coyote, and many smaller varieties of animal life.

Several tribal groups, including the Maidu people, were settled in the region when they were first encountered by Spanish and Mexican scouting expeditions in the early 18th century.

In the 1850s George W. Gridley, a wool grower and grain farmer who at the time was one of the largest landowners in Butte County, settled a 960-acre (390 ha) home ranch west of the town site that was to be named after him.

[10] In response to a "The Place Where Crops Never Fail" advertising campaign by the California Irrigated Land Company, members of The Church of Jesus Christ of Latter-day Saints began emigrating from the Rexburg, Idaho area to Gridley in November 1906.

By February of the following year the Gridley Branch of the church was organized and more Latter-day Saints continued coming to Gridley from Idaho, Nevada, Utah and other states, effectively turning this small farming community into a Mormon enclave.

[11] By the end of 1908 there were some 500 LDS settlers in the Gridley area and their first chapel was constructed on the west corner of Sycamore and Vermont Streets in 1912 with a seating capacity of 1,000—the largest LDS meetinghouse west of Salt Lake City at that time.

[13] In 2020, Gridley was the place where former NASA engineer and YouTube star Mark Rober achieved a world record of the World's Largest Elephant's Toothpaste Explosion with a height of 60 feet (18 m), before subsequently breaking the record again with a height of 250 feet (76 m) in 2021.

[14] According to the United States Census Bureau, the city has a total area of 2.1 square miles (5.4 km2), all land.

[citation needed] Gridley is located in the Central Valley, along California State Route 99, 56 miles (90 kilometers) north of Sacramento.