The community of Mittenaar came into being on 1 January 1972 with the merger of the formerly independent municipalities of Ballersbach, Bicken and Offenbach.

Ballersbach grew together over time from two centres, one around the Baalerstaa (Balder- or Baldurstein; "Baldur Stone") and the other to the south.

Only after the Second World War, when improved transport connections eliminated the village's remote location as a problem did a great upswing begin.

By participating in the contest "Unser Dorf soll schöner werden" ("Our village should become nicer"), Bellersdorf became known nationally.

The advantageous location, the quiet and the lack of through traffic have made Bellersdorf into the constituent community with the highest quality of living.

The nobles of Bicken and Dernbach were subject to the Count of Nassau in the struggle for ascendancy in the Herborner Mark.

In 1629 and 1630, thirty men and women (6 from Offenbach, 18 from Bicken and 6 from Ballersbach) were burnt at the stake by their own fellow villagers.

As for the oldest cultural monument, the tower at the Offenbach Church houses a bell from the year 1452, which has been in use uninterruptedly since then.

Mittenaar's civic coat of arms might heraldically be described thus: In sable a bend wavy sinister Or, above, a trefoil Or, below, two bars argent.

The arms show besides a wavy fess as a symbol for the Aar, which flows through the community, two charges of former noble families who held sway in what is now the municipal area: the cloverleaf for the Lords of Dernbach and, as mentioned earlier, the two bars of the Lords of Bicken.