Before European settlement, the land comprising modern-day Aetna Township was primarily inhabited by indigenous peoples of the Council of Three Fires, including the Ojibwe, Odawa, and Potawatomi. These tribes utilized the local waterways for transportation and the rich forests for hunting and gathering.
The township was formally established in the latter half of the 19th century during Michigan's great logging boom. The Little Muskegon River played a critical role in transporting timber out of the dense white pine forests that covered the region. As the land was rapidly cleared of timber, early settlers transitioned to agriculture, transforming the stumplands into productive family farms.
The village of Morley, platted around 1869 and incorporated in 1870, grew as a crucial railroad stop on the Grand Rapids and Indiana Railroad. The arrival of the railroad accelerated both the lumber export and the influx of new residents. Throughout the 20th century, Aetna Township settled into its current identity as a stable, agriculturally focused community, moving away from heavy industry toward farming and residential living.