Olalla is a small unincorporated community in Kitsap County, Washington, United States. It is located on Colvos Passage on Puget Sound, just north of the Pierce County county line. Olalla used to be as large as Port Orchard, the county seat of Kitsap County. Olalla was settled in its early years by a large number of Norwegian and other Scandinavian immigrants because of its similarities to their native countries. Noted as early as the 1860s, Olalla developed a commerce center by way of its good sea water access. The "old town" port located by the Olalla lagoon was made up of many business buildings, most on piers. Shipping and the mosquito fleet was very busy moving materials, goods and people.

Kitsap County is a county in the U.S. state of Washington. As of the 2020 census, its population was 275,611. Its county seat is Port Orchard; its largest city is Bremerton. The county, formed out of King County and Jefferson County on January 16, 1857, is named for Chief Kitsap of the Suquamish Tribe. Originally named Slaughter County, it was soon renamed.