When I saw that E Jansen Court fell within Jansen’s Addition to the City of Seattle, filed in 1889 by Mary Jansen, I thought “Ah, another case of a landowner naming a street after themselves,” though I did note it was rare to see a single woman’s, and no one else’s, name on such a plat. But once I got a good look at the plat map I realized that, as is often the case, things weren’t quite that simple.
There’s no Jansen Court on this map — instead, John Street keeps its name as it crosses Mulford Street (now 20th Avenue E). So what happened?
In 1954, E John Street — the arterial east of 21st Avenue E — and E Thomas Street — the arterial west of 20th — were connected directly to each other by lopping off a small part of Miller Playfield (creating Miller Triangle in the process). As part of this, a one-way extension of John was built east of 20th, connecting with the arterial just before 21st. But this meant what is now Jansen Court needed a new name (remember, it originally remained John Street after crossing 20th). The powers that be decided to simply name it after Mary Jansen (or her subdivision). So even though she hadn’t named it after herself, 65 years after she filed her plat Jansen finally had her name on a street sign.