The town of Walum is in Greenfield Township. It was named in 1902 for Martinius Wallum. Mr. Wallum was a pioneer, who lived about one-fourth mile north of the townsite.

According to L. Perrin, advertising manager, Northern Pacific Railroad, St. Paul, "It was named Wallum by a Northern Pacific railway roadmaster, J. E. Johnson, of Cooperstown at the suggestion of his friend, Claus Jackson. When objection was made to the name 'Wallum' the only change the objectors succeeded in making was to have the name spelled with only one 'l'."

Walum was settled in 1902; platted in 1905 land belonging originally to the homestead of Aslak Gunderson; plat filed on May 18, 1905 by his son Peter A. Gunderson. A railroad siding was built in September, 1902.

Walum post office was established on November 7, 1904 with Martin J. Massing as postmaster.

Source: Cooperstown Diamond Jubilee 1882-1957 Page 56