I was born in King County, Washington state, the same county where Seattle is located. The county was originally named after Vice President William Rufus de Vane King. In 1986 the county's name was changed from King County to (er...) King County! It is now officially named after Martin Luther King Jr., human rights advocate.
To read more, see: http://www.kingcounty.gov/operations/logo.aspx
People interested in human rights history may enjoy this piece by the BBC, comparing modern slavery with the historic variety:
"Slave Labor and Consumer Power: The Long View" http://www.bbc.co.uk/programmes/b06sgxg5
(Here's a piece about the King after whom the county was originally named, for anyone who's curious: William Rufus DeVane King)