Millgrove is an unincorporated community in Jackson Township, Blackford County, Indiana. Nearly all of the community's businesses have been closed for many years. Although the Blackford County Historical Society lists this community as a ghost town, homes are still maintained in the area.Like several other communities in the county, Millgrove originally thrived as a stop on a railroad line. Millgrove also participated in the Indiana Gas Boom, and the Millgrove Natural Gas Company was one of Blackford County's many gas companies that existed during the 1890s. The Gas Boom gradually ended during the beginning of the 20th century, and many small communities never recovered. During the next few decades, the quality of automobiles and roads improved—indirectly contributing to the decline of many small communities as consumers drove to larger cities, and railroads declined in importance.