Newcomer is an unincorporated community in Chariton County, in the U.S. state of Missouri.[1] A post office called Newcomer was established in 1886, and remained in operation until 1906.[2] W. F. Newcomer, an early postmaster, most likely gave the community his last name.This Chariton County, Missouri state location article is a stub.You can help Wikipedia by expanding it.