Other Green/White/Duwamish River Valley (South King County, North Pierce County) locations named for people:
Kent's original name was Titusville, after early settler James Henry Titus.
Renton is named after Captain William Renton, who financially backed the town and the coal company associated with it. (Shattuck Street is named for Charles D. Shattuck, who operated the Renton Coal Mine.)
Burien is named for Gottlieb von Boorian, who originally called his town "Sunnydale". He apparently came from somewhere in present Germany (guess that would be the German Empire or the Kaiserlich Deutsches Reich) to the Seattle are in 1880.
Georgetown District of Seattle is named for George M. Horton, son of Julius Horton who platted the original town (it was swallowed up by a growing Seattle early in the 20th century).
Unincorporated community of Christopher (between Kent and Auburn) named for Thomas Christopher, who established a post office there.
Unincorporated community of Thomas (also between Kent and Auburn) named for former Kentucky settler John M. Thomas, who called the land on which his community grew as "Pialsche" - named for a Native American friend that lived nearby.
Unincorporated community of O'Brien (near the present Kent Boeing plant) named for Morgan and Terence O'Brien, who led a community of Irish Catholics who settled at that location. They called their community the "White River Post Office." O"Brien eventually stuck.
Dieringer, between Pacific and Sumner on the East Valley Highway, apparently named for a Joseph Dieringer. Not at all sure if he was the engineer involved with the Dieringer Power Station (hydro power, generates electricity from water draining out of Lake Tapps to the White River in the valley below). There are a bunch of Dieringers that relocated to nearby Buckley from Wisconsin in the late 1800s, so he could be just the farmer who owned the most land near the power station (the town had a high school, which has recently been converted to a commercial building, though it is a historical landmark). Apparently the Dieringer School District was formed in 1890, and the power station and Lake Tapps were created in 1911, so that seems to support the latter idea.
Sumner, south of the county line, was named for U.S. Senator Charles Sumner from Massachusetts, who was assaulted by South Carolina Representative Preston Brooks in the midst of growing tensions between North and South prior to the Civil War.
Buckley - named for J. M. Buckley, Northern Pacific Railway superintendent.
Ravensdale - to the east of the Valleys, originally named Leary for John Leary, who sponsored the Leary Coal Company that was located near the town (renamed for a flock of ravens that fed on grains spilling from boxcars on the nearby Northern Pacific tracks).
Franklin - I want to say that this was named for Benjamin Franklin, but to be honest, I've not found anything to confirm that. It was a ghost town, one of my favorite places to walk around the woods, next to a huge gorge, and with a mine shaft that took about 10 minutes for a rock to hit bottom (they say 1,300 feet depth), and an abandoned overgrown graveyard (since cleared).
Oh, and the counties:
King County: Named for William Rufus DeVane King, who was Vice President for 45 days under President Franklin Pierce, but it was during those 45 days that Washington Territory was created.
Pierce County... will let you guess that one.
