How Watertown, South Dakota Got Its Name

Watertown, South Dakota, is named for Watertown, New York, the hometown of John E. Kemp, the first settler, who suggested the name. He and his brother Oscar brought the name west with them, and local tellings say they had to talk the railroad out of a different one to make it stick.

Where the name comes from

The Kemp brothers, John E. and Oscar P., came from Watertown, New York, before heading to Dakota Territory. A 1908 railroad guide to place names says the South Dakota town “was named at the suggestion of John E. Kemp, the first settler, who had emigrated from Watertown, New York,” and that the Winona and St. Peter Railroad Company platted it in 1878. The U.S. Geological Survey’s place-name record quotes the same book.

So the name isn’t about the lakes around town, even though there’s plenty of water nearby. It’s a transplant, carried halfway across the country from upstate New York.

The original Watertown has its own water story. The city of Watertown, New York, says its name came from the waterfalls and water power on the Black River, which runs through the middle of town.

The names it almost had

For a short while, the place went by the brothers’ last name. A 1956 state historical marker in town lists a “Kemp” post office established in March 1878, with Oscar P. Kemp as postmaster. The same marker says the county seat was first fixed at Kampeska, near the outlet of the lake of that name, and then moved to the newly established Watertown in October.

Local tellings add another twist. A Dakota News Now report says the railroad wanted to call the town Waterville, and the Kemps pushed back and insisted on Watertown, after the place they were from. A KELO-TV story makes the same point: the town was expected to be Waterville, but the Kemps won. We haven’t found an 1870s document that records the Waterville fight itself, so count it as local history passed down rather than something on paper.

One small mix-up in the old book

If you go digging, you’ll notice the 1908 guide can’t quite decide on John Kemp’s middle initial. Its entry for Codington County says the town was “named by John P. Kemp,” while its entry for the town itself says John E. Kemp. The town entry, the USGS record and the later local accounts all say John E. Oscar was the Kemp with the middle initial P., so the county entry looks like a slip, though we can’t prove where it came from.

The name on the main drag

The Kemps’ own name didn’t vanish when the post office changed. KELO-TV says Kemp Avenue, a main street through town, is named for the brothers. The town got their hometown’s name, and the street got theirs.

Sources & further reading

• W. H. Stennett, A History of the Origin of the Place Names Connected with the Chicago & North Western and Chicago, St. Paul, Minneapolis & Omaha Railways (1908). A public-domain railroad guide. Credits John E. Kemp with suggesting the name and dates the platting to 1878. Its county entry has the “John P. Kemp” slip.
• GNIS feature 1258841 (U.S. Geological Survey). The federal record for Watertown. Its history note quotes the 1908 guide, so it isn’t a separate source. It adds the founding in 1879 and incorporation in 1885.
• State historical marker no. 191 (1956). The Kemp post office of March 1878 with Oscar P. Kemp as postmaster, and the county seat’s move from Kampeska to Watertown. Read through the Historical Marker Database transcription.
• Dakota News Now, “Have you ever wondered: How did Watertown get its name?” The local telling of the Kemp brothers and the railroad’s “Waterville.”
• KELO-TV, “The story behind Kemp Avenue: Watertown’s history.” Waterville versus Watertown, and the brothers behind Kemp Avenue.
• City of Watertown, New York, “Watertown History.” Why the original Watertown is called that.