Wallace is a census-designated place (CDP) at the far west edge of Calaveras County, California, United States on State Route 12. The population was 403 at the 2010 census, up from 220 at the 2000 census.
On the 1883 map of the town site is the name of the surveyor, John Herbert Wallace. It has been widely assumed that he is the one the town is named after. However, according to historian Sal Manna in the July 2006 issue of Las Calaveras, the quarterly magazine of the Calaveras County Historical Society, the town is named for John Herbert Wallace's father, John Wallace, who was a well-known engineer and surveyor in the area. He had been elected San Joaquin County surveyor. John Wallace was also an elder brother of Alfred Russel Wallace, a leading 19th century British naturalist who independently developed a theory of natural selection around the same time as Charles Darwin. John Wallace had originally come to California for the California Gold Rush, but was unsuccessful as a miner.
According to the United States Census Bureau, the CDP has a total area of 4.4 square miles (11.4 km²), of which, 98.2% is land and 1.8% is water.