Diamond Creek Township covers an area of 144.4 square miles (374 km2).

[4] Hymer is a corruption of the surname of Frank and George Hegwer, original landowners.

[6][7][1] It was located on Middle Creek, 19 miles (31 km) north-west of Cottonwood Falls.

[7] Its mail and shipping point in the early 20th century was Antelope, in neighbouring Marion County, 9 miles (14 km) to its west.

[7] The community had a post office from 1874-08-24 until 1924-12-15, when it was replaced by rural free delivery.