History
The county was formed out of territory within Thurston County on December 22, 1852, by the Oregon Territory legislature, and was named after Alabama resident William R. King, Vice President under President Franklin Pierce. Seattle was made the county seat on January 11, 1853.
King County originally extended to the Olympic Peninsula. According to historian Bill Speidel, when peninsular prohibitionists threatened to shut down Seattle's saloons, Doc Maynard engineered a peninsular independence movement; King County lost what is now Kitsap County, but preserved its entertainment industry.
Logo, 1969-2007
On February 24, 1986, the King County Council passed Council Motion 6461, "setting forth the historical basis for the 'renaming' of King County in honor of Reverend Dr. Martin Luther King, Jr.". Because only the state can charter counties, this change was not made official until April 19, 2005, when Washington Governor Christine Gregoire signed Senate Bill 5332 into law.
Due primarily to the advocacy of council member Larry Gossett, the County Council voted on February 27, 2006 to change the county's logo from a royal crown to an image of King's face. On March 12, 2007, the new logo was unveiled.