Converse County was organized on March 9, 1888 in east central Wyoming.

Named after Amasa R. Converse, a Wyoming pioneer and Cheyenne banker, Converse County presently contains 4,255 square miles of land and 10 square miles of water. The county seat is Douglas.

When Converse County was first organized, it contained 6,624 square miles of land but that amount was reduced when Niobrara County was organized and carved out of Converse County in 1911.