Lewis and Clark landed on Blalock Island in the Columbia River near the modern location of Richland in 1805 and found Indian villages dating back to prehistoric times. For the next half a century fur trade kept the locals busy, with canoes from the Hudson Bay Company traveling up and down the Columbia River. The extensive grasslands of the area were cut for hay by the men of Fort Walla Walla (now known as Wallula), and the hay was used to feed their growing herds of livestock.
Washington Territory was created in 1853, and Governor Isaac Stevens planned a cross-state railway leading up to the Yakima Valley and across the Snoqualmie Pass to Puget Sound. At about this same time, J.B. Nelson built the first settler’s cabin near the mouth of the Yakima River. In 1868, E. Bird moved about 300 head of cattle into the area where Richland is now, and Smith Barnum built his home just south of the Yakima River.
In 1875, Mr. Barnum’s house was made a station along a stage line between Wallula City and Yakima City. Only six years later, in 1881, James Kinney homesteaded in an area now known as Prosser City.
James was later credited with giving the Horse Heaven Hills their name. Also in 1881, Colonel William Farrand Prosser filed a homestead claim in the same area near Yakima Falls. He obtained the post office for the town, with his wife serving as postmistress. When Mrs. Prosser wrote to the Post Office Department to request the designation of Prosser Falls for the post office, they replied that the word “Falls” was in too many communities, and another would just add to the confusion. The word “Falls” was dropped, and Prosser City was born.
Construction of the Northern Pacific Railroad’s main line through the Yakima Valley was started in 1883, with construction camps located in Kennewick, Kiona, and Prosser. School districts were established in Prosser in 1884 and six months later in Kennewick to serve the children of the construction camps.
In 1899, Prosser was incorporated and became the seat of Benton County when it was formed in 1905. The railroad and irrigation in the early 1900s played a huge part in the flourishing town’s history.
Twenty miles north of Richland, the Hanford Atomic Reservation was established in 1943 because of an abundance of water and electricity. The nuclear industry has been a cause of much growth since then. In the intervening time, Hanford has become a complex for energy research and development labs as well as a center for nuclear generation projects. It is the major source of employment for the entire county.
In 1953, the McNary Dam was built on the Columbia River about 30 miles south of Prosser and has allowed ocean-going barge traffic to head as far upstream as the city of Richland.
In the words of the Prosser Chamber of Commerce: “Prosser now has a population of just under 5,000, and the local economy centers around agriculture. Prosser today is a tranquil oasis of green with its peaceful river meandering through the velvet hills that cradle Prosser's tree-lined streets. This clean, attractive town is friendly to all and features old-fashioned light poles and cobbled sidewalks. Prosser has even been dubbed the "Birthplace of the Washington Wine Industry." Almost 300 sunny days annually lend way to a variety of outdoor activities including hunting, fishing, camping, hiking, boating, and golf. “