Douglas County (see map below) was created from Lincoln County November 28, 1883 and sits on the eastern side of the Columbia River with neighboring Chelan County on the west side of the river. The county was named for American statesman Stephen A. Douglas (1813-1861), Abraham Lincoln's opponent in the 1860 presidential race. A senator from Illinois, Douglas was the chairman of the U.S. Commission on Territories at the time Washington Territory was established. Later, on February 24, 1909, Grant County would be formed out of Douglas County. Douglas County is located in North Central Washington and is predominantly rural. It is bordered by Chelan County to the west, Okanogan County to the north, Grant County to the east/southeast, and a tiny portion of Kittitas County to the south. Huge floods during the Ice Age shaped the land forming deep coulees (canyons). In 1987 bone and stone artifacts from the Paleolithic period were discovered in an apple orchard in East Wenatchee. It included the largest spear points of Ice Age Clovis Man yet discovered.

According to US Census Bureau estimates in 2020, the county population was about 43,560. The county seat is in the town of Waterville.

The city of Bridgeport, settled in the late 1800s, is located near the Chief Joseph Dam. It was originally called Westfield with the earliest settlers being Chinese miners panning for gold along the banks of the Columbia River. The town was purchased in 1892 by developers who renamed it after Bridgeport, Connecticut from where they came. Incorporation took place in 1910. Chief Joseph Dam was originally called Foster Creek Dam. The nearby Rufus Woods Lake is an artificial lake created by the backwater from the dam. Clyde Pangborn, American aviator and barnstormer, was born in Bridgeport. In 1931, he and his co-pilot flew their plane, Miss Veedol, on the first successful non-stop flight from Japan across the Pacific Ocean to a belly landing in East Wenatchee. Bridgeport Timeline.

The city of East Wenatchee is separated from the city of Wenatchee (in Chelan County) by the Columbia River and the county line. The first European in the area was said to be David Thompson who in 1811, stopped on the banks of the Columbia River to trade fur with tribal horsemen. In 1888 the first white homesteader, Harry Patterson, put down roots by staking the first homestead claim and others slowly followed. The only way to cross the Columbia at that time was by an unreliable ferry at the foot of Orondo Street in Wenatchee. In 1908, the Columbia River Bridge was built connecting it to Wenatchee, allowing access to irrigation water. Within a short time apple orchards became  prevalent in East Wenatchee. In 1987, orchard workers found prehistoric Clovis spear points, dating back about 12,000 years, in an apple orchard. In 1935, the town of about 300 voted to incorporate. In 1950, still very rural, Alcoa built a huge plant in Wenatchee and workers built homes in East Wenatchee. In 1951, a more modern bridge was built, now known as the George Sellar Bridge, connecting the two cities spurring more growth. East Wenatchee Timeline.

The community of Rock Island was incorporated in 1930, previously having been settled in the late 1800s and known as Hammond. The first permanent settler was James Keane who arrived in 1887. Due to the Great Northern Railway changing locations, Keane moved the townsite 2.5 miles and named it Rock Island. This would become an important site for the railroad, however, the railroad would move away when the first bridge crossed the Columbia in Wenatchee leaving Rock Island with few jobs in town. It would become a booming town again with the construction of the nearby Rock Island Dam, the first dam on the Columbia River, in January, 1930. Construction was completed at the end of 1931. In 1950, with the Alcoa plant being built almost directly across the river in Malaga, requiring six more power generators to be built bringing the total to 11 generators. Today, there are 19 generators online with the capacity to serve nearly half a million people. Rock Island Timeline.

The town of Coulee Dam is located partly in Douglas, Grant, and Okanogan Counties and was founded by the U.S. government in 1933 to serve as construction headquarters for the Grand Coulee Dam. Coulee Dam was sold to the public in 1957 and incorporated in 1959. It is the headquarters for the Lake Roosevelt National Recreation Area, created by the dam and named for President Franklin D. Roosevelt. Lake Roosevelt is the site of one of the world's largest man-made piles of sand which remaine from dam construction.

Mansfield sits about 60 miles northeast of East Wenatchee. It was settled in 1889 by Robert E. Darling from Mansfield, Ohio. In 1909 with the arrival of the Great Northern Railroad, Mansfield was booming and incorporated in 1911. Fires, drought, and the Great Depression changed Mansfield but due to  enormous wheat production is still known today as a wheat town with a population of about 350. In 1985, railroad repairs were needed but the railroad deemed it too expensive and pulled out. Mansfield would be known as the town at the end of the rails and wheat crops would subsequently be transported by semi-trucks. Mansfield is well known for hang gliding due to its favorable summer weather, and cross country skiers in winter. Mansfield Timeline.

The county seat of Waterville sits 28 miles northeast of East Wenatchee, atop the high plateau of the Big Bend of the Columbia River. Its elevation of 2,650 feet is the highest of all incorporated towns in Washington state with dramatic views of Badger Mountain to the south and the Cascade Mountains to the west. Pioneers settled here during the early 1880s, with the first squatter's claim taken out by Stephen Boise in 1883. In 1887, Waterville was named the county seat and a post office was established with mail arriving by stagecoach from Spokane and Ellensburg. During severe winters, stage coaches could not get through and mail was brought by toboggan or on snowshoes until normal delivery could resume. Waterville was incorporated in 1889 around the same time Washington Territory became the 42nd state. The 1900 census put Waterville's population at 482. Today, the population sits at around 1,200. Waterville hosts the annual Douglas County Fair. Waterville Timeline.