In 1844, Township 1 north, in range 7 west, was named Assyria on its organization in the state of Michigan. It is found in the southeastern corner of Barry County, having Maple Grove township on the north, Calhoun County on the south, Eaton County on the east, and Johnstown township on the west. When first settled the township consisted mainly of oak-openings, with tracts of hard-wood timber in the eastern part.

Old settlers say it was a most attractive-looking country, particularly in early summer, when wild-flowers covered the earth in profusion, and the numerous glades offered a charming perspective in every direction. Assyria is reckoned an excellent agricultural township, particularly in the production of wheat, of which the yield is said to average 20 bushels per acre. In the west and southwest the surface is rough, and there is some waste land, but generally the surface is level and the soil rich. Assyria is a rural township.