Rock Island is a city in Douglas County, Washington, United States. It is allocation of the Wenatchee–East Wenatchee Metropolitan Statistical Area. The population was 788 at the 2010 census.

Rock Island was officially incorporated upon November 3, 1930. The area of Rock Island was used by Native American tribes for fishing and crossing of the Columbia River due to the easy to use Rock Island Rapids prior to treaty of the Washington Territory.

The site had been previously settled in the late 19th century and was known as Hammond; early maps sometimes decree the city as Hammond P.O. (Post Office) or Power City. In the teacup valley in which Rock Island is currently located, two men, Ingraham and McBride, opened a trading proclaim in the yet to be 1860s. Their patrons were local Native Americans, who often fished that stretch of the Columbia later the fish were running. The two pioneering men would complex move their herald to the mouth of the Wenatchee River, leaving little trace of their stay.

The most notable figure in Rock Island’s founding is James E. Keane. As the first surviving settler to the Rock Island area, James Keane arrived past a crew of men in 1887. Keane planned to build a home and enhance the home that he had acquired through the Homestead, Pre-emption, and Desert Acts. Four years later, the Great Northern Railroad made its first survey of the Place and began construction toward the valley from the east. One half mile upriver from the renowned Rock Island Rapids, Mr. Keane platted a townsite he named Hammond.

Hammond was located nearly 2.5 miles south of the present site of the City of Rock Island due to changes in planning by the Great Northern Railway. Keane moved his townsite to this new Place and named it Rock Island, named aptly for the rock islands in the Columbia River close the site. Between 1891 and 1893, Rock Island became a town of considerable importance for the railroad. The mammoth steel bridge that was built across the Columbia drew many laborers to the area, and the small town boomed. Several stores popped up to meet the needs of the workers, and the Rock Island Sun newspaper began publication.