It is named for John Alpaugh, one of the officers of the Home Extension Colony which reclaimed (or land speculated on) the land the town is built on.
Alpaugh's location (once also called Hog Island, Root Island, and Atwell's Island) was once either on an island or a narrow peninsula near the south end of the huge and rich Tulare Lake. A.J. Atwell was a Visalia attorney (and newspaper owner) who raised hogs on the island,. .The lake at different times supported a very large Indian population, a commercial fishery, herds of tule elk, countless game birds, and much more. The island was a regular port of call for the lake's commercial ferry service. The last time the lake was brim full and overflowed into the San Joaquin River to the sea was 1878. Water diversions of its source waters have since caused the lake to shrink into the tiny remnant of today. Local efforts are underway (in 2011) to increase the lake's size for water storage and wildlife.