The Kearny family settled the Keyport area in 1714. Their plantation, which featured timber and produce, and as many as 70 slaves and two sloops, prospered for over a century. The plantation was then divided and auctioned off, and Keyport was established in 1830. From then until about 1900, it was a major shipping center. In the mid-1800's, it was a major ship-building center as well.
From 1917 to 1937, Keyport was home to Aeromarine Plan & Motor Company, one of the pioneers in aviation. They introduced the first electric starter, first international airline, first metal-clad plane, and numerous other "firsts" in aviation.