Harmony Society, religious society founded by German Separatists under the leadership of George Rapp. The Harmonists (or Rappites) held property in common and subscribed to the austere doctrines of their leader, including that of celibacy. In 1805 the society founded the village of Harmony, Pa., and developed it into a prosperous agricultural and industrial community. Led by Rapp, the Harmonists moved in 1814–15 to Indiana and founded another Harmony. They prospered there too, but in 1825 they sold their holdings to Robert Owen (see New Harmony) and returned to Pennsylvania to create their third village at Economy (now Ambridge), NW of Pittsburgh. In 1832 a part of the colony, under "Count Leon," a German adventurer, withdrew to form a separate community. The society was weakened by the death of Rapp (1847), dwindled as the members grew older, and went out of existence after 1906.
See studies by A. Williams (1866, repr. 1971); J. S. Duss (1943), and K. J. R. Arndt (2 vol., 1972).