Ōhawe is a coastal settlement 8 km west of Hāwera at the mouth of the Waingongoro River. Ōhawe is one of New Zealand’s earliest settled places. The first people hunted several species of moa and other birds here about 1300 AD. Ōhawe township was founded as a military settlement. In 1865 the 57th Regiment under the command of General Duncan Cameron reached the river as they advanced up the west coast from Whanganui. Two redoubts were constructed – one on each side of the river mouth. The short-lived ‘Republic of Hāwera’ was based in Ōhawe. It was founded by James Livingston in 1879 out of frustration at the lack of government action after Te Whiti’s followers ploughed up his land. Volunteers patrolled the area and prevented further ploughing.
Ōhawe means place of; hawe: bend in the river or path. In this case the reference is presumably to the winding course of the Waingongoro River.
Thanks to https://nzhistory.govt.nz/keyword/ohawe