The actual settlement probably began in the second half of the first millennium, when a number of Frankish settlements arose in the Rhine-Main-Neckar area. The place name in its old spelling "Araheiligon" is mentioned for the first time in an undated interest register of
Seligenstadt Abbey, which an unknown scribe probably added to a 9th-century gospel book of the monastery around the year 1000. The
Thirty Years' War shook Arheilgen hard. As early as 1622, the troops of
Count von Mansfeld robbed all the houses and the church. In January 1635, the village was almost completely burned down by French troops. Only a few houses remained. The surviving residents fled behind the supposedly safe walls of nearby Darmstadt, where many of them died of the
plague. At the end of the war in 1648, only about 12 families were left to rebuild the community. ==Seal and coat of arms==