Dilworth started out as a village and division point of the Northern Pacific railway in 1883 and was named by officers of that railway company. It was originally named Richardson but in November 1884 it was changed to Dilworth to honor Joseph Dilworth of Pittsburgh, Pennsylvania who was a coffee importer, a manufacturer/supplier of railroad supplies, and an organizer and stockholder of the Northern Pacific Railroad who had traveled into the area of western Minnesota and North Dakota several times. The origin of Richardson could not be found but interesting enough the maiden name of Dilworth's wife was Richardson. In the 1899 map below, it shows he owned a great amount of land near the village.
Dilworth did not receive a post office until 1907.