Snohomish County // is a county located in the U.S. state of Washington. It is named after the Snohomish tribe. Since 2010, the county's population has grown from 713,335 to 733,036 residents (2012), making it one of the fastest-growing in the state, ranking third in overall population after King (2,007,440) and Pierce (811,681) counties (per 2012 Estimate figures). The county seat is Everett, the county's largest city in population.
Snohomish County was created out of Island County on January 14, 1861.