Bartle, IndianaBartle is an unincorporated community in [Polk Township, Washington County, Indiana|Washington County, Indiana|Polk Township], Washington County, in the U.S. state of Indiana.HistoryA post office was established at Bartle in 1880, and remained in operation until it was discontinued in 1906. In 1900, the population was 18.GeographyBartle is located in Washington County, Indiana along the Blue River at.