Beaver is a city in and the county seat of Beaver County in southwestern Utah, United States. The population was 3,592 at the 2020 census, up from the 2010 figure of 3,112.

Indigenous peoples lived in the area for thousands of years, as demonstrated by archeological evidence. A number of identified prehistoric sites have been found in Beaver County, dating to the Archaic and Sevier Fremont periods. A prehistoric obsidian quarry site has been identified in the nearby Mineral Mountains.

The historic Southern Paiute inhabited the region well before encountering the first European explorers. The 1776 Dominguez–Escalante Expedition is the first known European exploration in this area. ^{[citation needed]}

In 1847–1848, Mormons from the United States developed a trade route through the Beaver River valley between their new settlements at Salt Lake City in the Utah Territory and Los Angeles, which was still part of Alta California, Mexico. The original route crossed the river three miles downstream from Beaver at the site that later was developed as Greenville. This route became known during the California Gold Rush as the Southern Route of the California Trail. Later called the Mormon Road or California Road, it passed over the Black Mountains between the crossing and Muley Point. Following the United States' victory in the Mexican–American War (1846–1848), it took over California and the Southwest.

In 1855, as part of improvements, the Mormon Road over the Black Mountains was realigned eastward. It was routed from the site that developed as Beaver to Muley Point through more wagon-friendly terrain in Nevershine Hollow and over Beaver Ridge into the canyon of Fremont Wash, rejoining the original road above Muley Point. This road became a winter commercial wagon road, known in California as the Los Angeles – Salt Lake Road, and in Mormon settlements in Utah and Arizona Territory (now southern Nevada) as the California Road.

Beaver was settled in 1856 by Mormon pioneers traveling this road; it was one of a string of Mormon settlements along the road through Utah. By design, these settlements were located a day's ride on horseback apart, which explains the regularity of their spacing. They were generally 30 miles (48 km) apart. Where intervening settlements failed or were absorbed, they became 60 miles (97 km) apart. Beaver was developed between the settlements in the Pahvant Valley and those in the Parowan Valley.

In 1873 the US Army established Fort Cameron, two miles from Beaver, because of Indian raids on the area Mormon settlements. To serve this isolated area, the territorial government placed the Second Judicial Court of the Utah Territory in Beaver from 1870 until 1896, when Utah became a state. Also included in this court's jurisdiction were Iron, Washington, Kane, Garfield, and Piute counties. ^{[citation needed]}

In 1856, Mormons migrated to the Beaver Valley from Parowan to the south. George A. Smith called a council meeting in February 1856, and Simeon F. Howd was elected as presiding elder and Edward W. Thompson as clerk. In 1858, numerous migrants from San Bernardino, California, settled here. In December 1859, W. W. Willis and P. K. Smith were authorized by the council to build a sawmill and gristmill on North Creek, and given control of all water on the mill site. By 1869, the Mormon settlers in Beaver were numerous enough to organize a stake. The first stake president was John Murdock.