The district was created in 1975 by merging the previous districts of Darmstadt and Dieburg. In 1963 the district was twinned with the district ofNorth East Derbyshire, England, in 1990 with the districtZwickauer Land inSaxony, Germany, and in 1995 with theMladá Boleslav region in theCzech Republic.
The coat of arms show a lion in the top part, taken from the coat of arms of the counts of Katzenelnbogen. The lion holds aWheel of Mainz, the symbol of state ofMainz. Both owned big parts of the districts area in the past. The 23 stars in the bottom represent the municipalities of the county.