 On May 31, 1867, a post office was established at the ferry and named Martinsville, which was renamed Emmettsville on October 31, 1868; postal officials shortened the name of the post office to Emmett in 1885.Census data for the area shows Squaw Creek Precinct under Boise County with a population of 30 in 1870.Ada County did not separately return precincts at that census.