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.

[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.

By design, these settlements were located a day's ride on horseback apart, which explains the regularity of their spacing.

In 1873 the US Army established Fort Cameron, two miles from Beaver, because of Indian raids on the area Mormon settlements.

Also included in this court's jurisdiction were Iron, Washington, Kane, Garfield, and Piute counties.

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.

[5] 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.

[7] During the 1870s, settlers made an effort to establish a woolen mill, a tannery, and a dairy industry.

[citation needed] A hydroelectric generation plant was constructed on the Beaver River early in the 20th century.

The plant continues to provide a large part of Beaver's power requirements today.

Utah State Route 153 heads east from Beaver across the Tushar Mountains 40 mi (64 km) to Junction, and Utah State Route 21 runs west through the Beaver River Valley 17 mi (27 km) to Minersville.

According to the United States Census Bureau, the city has a total area of 6.5 sq mi (16.8 km2), all land.

Beaver has a typical Intermountain Region cool semi-arid climate (Köppen BSk), bordering on a humid continental climate (Dfb), with summers characterized by hot days and chilly nights, and cold winters with moderate snowfall.

During the summer, days are hot and usually dry, though on occasions, as in July 1936 – the wettest month on record with 5.76 inches or 146.3 millimetres – monsoonal weather can bring heavy thunderstorms from the Gulf of California.