Kißlegg was first mentioned in the year 824 as Ratpotiscella. On February 28, 1394, King Wenceslas granted the lordships the right to hold a market and both high and low jurisdiction in Prague. In 1548, 1704, and 1756, Kißlegg was almost completely destroyed by fire. The chronicle reports famines in the years 1614, 1635, and 1682. Kißlegg finally became part of the Kingdom of Württemberg in 1806. In 1820, the independent communities of Kißlegg, Sommersried, Emmelhofen, and Wiggenreute were formed. On April 1, 1934, they were merged into the overall community of Kißlegg. In 1972, Immenried and Waltershofen were incorporated.