Some of the residents of Lindström, Minn., did not even realize that the umlauts were gone.

For decades, the cheerful twin dots had hovered over the “o” in Lindström on the green highway signs that welcomed visitors to the small hamlet — population, 4,442 — that had been settled by Swedish immigrants in the 1850s.

After a highway project in 2012, the signs came down and were replaced with new ones. According to a city official, the Minnesota Department of Transportation denied the town’s request that the umlauts remain, citing a rule that road signs have only letters in a standard alphabet. So in a change that irritated some Sweden-adoring people here, Lindström became Lindstrom.

But in an announcement that was indignant, a little quirky and very Minnesotan, the governor intervened on Wednesday, releasing a statement that promised that the umlauts on the signs would be restored, and fast. “Nonsensical rules like this are exactly why people get frustrated with government,” Gov. Mark Dayton, a Democrat, said in the statement. “Even if I have to drive to Lindström and paint the umlauts on the city limit signs myself, I’ll do it.”

Lena Norrman, a lecturer for Swedish and Scandinavian studies at the University of Minnesota, said that linguistically, the loss is significant. “These are not just two little dots,” said the Swedish native. “It’s a significant letter with its own sound. You can’t just take them away.” She added that while the term umlaut is often used, many linguists consider the “ö” in modern Swedish to be a distinct letter.