The class is named after a town of Thomaston, Maine, which was the home of General Henry Knox, the first Secretary of War to serve under the United States Constitution.

[3] The class was designed to be able to transport: The dock was covered by removable segments that were able to carry the weight of two medium helicopters.

The machinery spaces were located underneath the dock, in contrast to the earlier Ashland class, where the machinery spaces were located to port and starboard of the dock.

Originally, all ships were armed with eight 3"/50 caliber gun Mark 33 twin mounts.

All ships were decommissioned by the U.S. Navy between 1983 and 1990, Alamo and Hermitage were sold to Brazil in 1989–1990.