A toll bridge across the Umatilla River at the townsite formed an important link in the westward migration via the Oregon Trail. The town was named for a United States Senator from Ohio, George Hunt Pendleton, the Vice Presidential candidate with McClellan against Abraham Lincoln in 1864. Agriculture, light manufacturing and tourism activities form the principal industries in and around Pendleton. Dry land farming is practiced in the Pendleton area, but considerable acreage of former desert land to the west of town has been brought under irrigation by pumping water mainly from the nearby Columbia River.
Cattle raising and forestry are other major industries in the area.
The Pendleton Woolen Mills, famous for wool blankets of Indian design, was founded in the early 1900's. and continues to be one of the chief industries and tourist attractions. The area around Pendleton is semi-arid, with very warm and dry summers and cool, moist winters. Average July highs are near 90 with overnight lows around 60. January's average highs and lows are in the upper 30s and mid 20s. The growing season averages 161 days.