MYNORTHWEST HISTORY

Seattle’s Lake Union was named at July 4 picnic in 1854

Jul 4, 2023, 6:25 AM | Updated: 11:05 am

The old story goes that the names of Lake Union and Lake Washington were suggested during a rousing speech given at a 4th of July picnic in Seattle in 1854. But is there any proof it happened this way?

Most of the details of this story come from Seattle historian Clarence Bagley. In 1916, he authored a three-volume Seattle history which amounts to the first in-depth look at the city’s past. In the now yellowing pages of one of those 107-year-old volumes, Bagley describes an Independence Day picnic held at the homestead of Thomas Mercer on July 4, 1854.


Thanks to changes in the lakeshore, the exact location is hard to pinpoint, but one interpretation would put those long-ago patriotic festivities a little bit south and west of where Seattle’s Museum of History and Industry (MOHAI) is now, at the site of the Armory at Lake Union Park.

Of course, for time immemorial, before settlers came, most lakes and other geographic features in and around what became Seattle had names already bestowed by and used for generations by Duwamish and other Indigenous peoples. But, Indigenous languages were an oral tradition with no written records. The arrival of non-Native settlers, with their real estate documents, maps, and other expressions of written language, meant, among other more destructive changes, a new layer of names on the land.

The role of Thomas Mercer

Thomas Mercer was from Ohio, and he had lived in Illinois before arriving in Seattle in 1853. He had recently been widowed on the Oregon Trail and was now in his 40s and the single parent of four girls.

As Bagley’s “naming picnic” story goes, Mercer was also something of a visionary. In his speech in July 1854, Mercer told those gathered the salt water of Puget Sound would one day connect to the freshwater of Lake Washington, and the two bodies of water would be linked by way of the small lake in between.

Thus, Lake “Union” was the name Mercer proposed. He also proposed the name for Lake Washington that day, too, by the way – since Washington Territory, rather than Columbia Territory, had been created by Congress just a year earlier.

Bagley writes:

On July 4, 1854, a large portion of the then small settlement at Seattle took part in a patriotic outing at Lake Union, known only by various Indian (Chinuk Wawa) names, the principle of which was ‘tenas Chuck,’ or ‘little lake or waters,’ as Lake Washington was known as ‘hyas Chuck’ or ‘big waters.’

On this occasion, Thomas Mercer called the citizens’ attention to the propriety of providing suitable names for the lakes, and suggested naming the larger lake after the ‘father of our country’ for whom the recently created territory had also been called, and proposed the name of “Union” for the smaller as befitting the embodiment of the territory with the United States, as well as the possibility of ‘this little body of water sometime providing a connecting link, uniting the larger lake in Puget Sound.’

The suggestion of Mr. Mercer resulted in a meeting held in the town a few weeks later at which both names suggested by him were enthusiastically adopted. And his vision of the eventual linking of Lake Union with Puget Sound and Lake Washington is now an accomplished reality.

It took a while – more than 60 years – but the vision for the “union” between fresh and salt water finally came true on July 4, 1917, when the Ballard Locks and Lake Washington Ship Canal were officially dedicated.

One additional reason that Bagley says Mercer took into account in naming Lake Union – and which doesn’t get mentioned as much as the fresh-and-salt-water link – is that “Union” was also a nod to Washington Territory someday becoming a state and joining the Union.

Bagley’s story can sound a little too neat and tidy and almost like a myth. This doesn’t mean the story is not true, of course. But, it seemed worthwhile to check with some local experts to see if they could verify the Thomas Mercer Lake Union story.

Other Lake Union perspectives

David B. Williams is the author of many books about Northwest history, including a book about the development of the Lake Washington Ship Canal.

“Hard to say if it is true or not,” Williams wrote in an email. “I don’t remember being able to find anything in the newspaper or journals or letters contemporaneous with the event.”

Williams also shared a copy of a seven-page letter (or historical notes, really) that Thomas Mercer sent to the historian George Bancroft sometime in the late 19th century.

On the last page, Mercer doesn’t mention a picnic, exactly. He says only:

Several of the neighbors in Seattle met in 1854 to suggest names for their two large lakes. I suggested for one the name of Washington, as being the largest in the Territory, and for the other of the name of Union on account of its locality for some time it would be a connection between Lake Washington and the Bay. The names were established after some little opposition.

Williams describes Thomas Mercer as a keen observer and a bit of a diplomat.

“Mercer had pretty good relations with the Native people of the area and surely would have been aware of them, particularly the Suquamish, traveling between Puget Sound and Lake Washington via Lake Union,” Williams wrote. “So, what he proposed was simply the modern manifestation of an idea that has been around for at least 10,000 years: both salt and fresh water have important resources to use, so finding a good travel route between them is a good thing.”

Coll Thrush is a professor at the University of British Columbia in Vancouver, British Columbia, and the author of “Native Seattle: Histories from the Crossing Over Place.”

Thrush is not sure if the “naming picnic” really happened the way Bagley describes it. Like David B. Williams, Thrush is also not sure that Mercers “union” idea for the bodies of fresh water was all that new or original.

“From the indigenous geography of the place, we can already see that the three lakes – Lake Union, Lake Washington, and Lake Sammamish – were already connected linguistically; they all had names that were very, very similar and related to each other,” Thrush told KIRO Newsradio.

“’Ha-ha-choo’ for Lake Union, which meant ‘small freshwater’; ‘Ha-choo’ for ‘big freshwater’ Lake Washington; and ‘Ha-a-choo’ [for] ‘second big water’ for Lake Sammamish,” Thrush said, citing the Lushootseed names and modern phonetic spelling for the three lakes.

“Duwamish people and neighboring peoples already had a geography that connected those lakes to each other,” Thrush continued. “So, it’s quite possible it wasn’t Thomas Mercer’s idea in the first place.”

Coll Thrush says the Duwamish were also likely aware of the already existing link between the freshwater of what Lake Union and the salt water of Puget Sound because a small salmon-bearing stream connected the two places along what’s now, essentially, the route of the “Fremont Cut” portion of the Lake Washington Ship Canal.

Myth or otherwise, there’s no sense knocking around the old Seattle pioneer (and longtime judge) Tom Mercer. He died in May 1898 at age 85 and, other than his notes to George Bancroft, does not appear to have put much effort into promoting the “naming picnic” story. And, when it comes to naming and Thomas Mercer, maybe we should give the guy a break since it’s his name (and his street) at the heart of the “Mercer Mess.”

A family’s connection to a history book

Still, there is one more relevant detail worth considering. As stated above, it’s from Bagley’s Seattle history book that we get most of the details of the “naming picnic” story. As noted above, Thomas Mercer had four daughters, including one named Alice Mercer.

Alice Mercer’s husband? Yes, you guessed it, Clarence Bagley, who perhaps had inside information from his father-in-law about a certain picnic or who maybe felt like paying tribute to his wife’s late father in print with an embellished story.

Or maybe it was a little of both, and what Bagley ultimately created was a “union” of fact and myth.

You can hear Feliks every Wednesday and Friday morning on Seattle’s Morning News with Dave Ross and Colleen O’Brien, read more from him here, and subscribe to The Resident Historian Podcast here. If you have a story idea, please email Feliks here.

seattle teachers union president...

Jake Skorheim and Spike O'Neill Show

‘Is this union acting in the best interest of students?’: Jake raises alarm over Seattle teachers union president’s alleged abuse

As Seattle teachers weigh whether to strike, KIRO host Jake Skorheim said he can't stop thinking about the person leading the negotiations.

47 minutes ago

Smoke billows from the Plaskett Fire near Big Sur, Calif, Thursday, Aug. 27, 2026. (AP Photo/Nic Co...

Associated Press

2 wildfires burn along California’s scenic Big Sur coast

BIG SUR, Calif. (AP) — Fire crews with water-dropping aircraft attacked a small wildfire that prompted new evacuations Thursday along California’s remote Big Sur coast, where a much larger blaze has been burning for nearly three weeks. The Plaskett Fire erupted the previous day in steep terrain in Monterey County near Highway 1. Officials briefly […]

1 hour ago

Seattle Police bonuses hiring incentives...

Frank Lenzi

Seattle Police Department scraps $50K hiring bonuses Sept. 1 as staffing crisis deepens

The Seattle Police Department (SPD) will no longer offer hiring bonuses as of September 1, citing budget concerns.

1 hour ago

man killed goose...

Jack Bilyeu, KIRO 7 News

Seattle Animal Shelter looking for man who killed goose at South Lake Union

The Seattle Animal Shelter is investigating an animal cruelty case after a man killed a goose on South Lake Union.

2 hours ago

Sound Transit Light Rail Fare Gates...

Frank Lenzi

Sound Transit approves fare gates at 14 light rail stations, eyes up to $83M in new revenue

Sound Transit plans to bring fare gates to up to 14 of its light rail stations — a move that could generate nearly $83 million a year in net revenue.

2 hours ago

brush fire SR 104...

Jason Sutich

Overnight closure likely on SR 104 after brush fire spreads to wires in Jefferson County

The westbound direction of SR 104 near Southpoint Road is blocked Thursday due to a brush fire that has spread to telephone wires.

3 hours ago

Seattle’s Lake Union was named at July 4 picnic in 1854