In the 1st century AD, the Roman Empire under Emperor Domitian expanded its territory in Germania at the expense of the local Chatti.

Around 750 meters southwest of this area the Romans built a castrum, later known as Kastell Arnsburg/Alteburg [de], which housed a cohort of around 500 soldiers.

One possibility is that it derived from Castellum Hadrianum (Hadriansburg) after the Roman Emperor Hadrian during whose reign the castrum was built.

[2] The first local lord known by name is Kuno von Arnsburg, who served Emperor Heinrich IV as a Ministerialis in 1057.

Konrad II exchanged properties with Fulda Abbey, receiving the land of Münzenberg Castle not far from Arnsburg.

[4] In 1150/1 Konrad II and his wife Luitgard set up a Benedictine monastery known as Altenburg and provided it with rich gifts.

The position on a hill was in line with Benedictine standards and the Roman ruins could serve as a source of building materials.

Heinrich, Archbishop of Mainz, who was the ecclesiastical superior of the monastery, confirmed its establishment in a document dating to February or March 1151.

[5] Due to a lack of progress on the Benedictine house, Kuno I von Münzenberg eventually contacted the abbot of Siegburg Abbey, Nikolaus, and managed to convince him to withdraw the monks from Altenburg.

They also refrained from exercising the rights of ownership over newly founded abbeys, leaving them to the responsible (Arch-)Bishop.

Cistercians also usually asked to be exempted from the Vogt system, whereby the secular ruler retained some administrative or judicial rights.

The general chapter of the Cistercians then ordered the abbot of Eberbach Abbey, Gerhard, to send monks to Arnsburg.

The founder had reserved only the status of "patron" in 1174 and in 1219 Emperor Friedrich II just granted his "protection" to the abbey, which was projected from Friedberg Castle.

Nevertheless, the Vogt rights retained by the secular lords created some tensions of time, as the family of Falkenstein-Eppstein and then the Grafen von Solms inherited the lordship over the area from the Münzenbergers.

[9] By the late 14th century, the abbey owned property in (or rights to income from) 270 locations between Fulda, Wetzlar, Gelnhausen and Mainz.

[11] In 1404, the convent denied Archbishop John II of Nassau financial support and as a consequence he seized the abbey's properties in the Rheingau, Wetterau and on the Main river.

In addition, during the confrontation a reported 26 farms were burned and damages totaling 73,000 Gulden were inflicted on abbey property.

The Solms family claimed sovereignty over the abbey, which insisted that it enjoyed imperial immediacy (Reichsunmittelbarkeit) and was therefore free from any other authority than the Emperor.

In 1623, the Gothic Heiligkreuzkapelle (chapel of the holy cross) on the Hainfeld (built 1399) was desecrated and plundered by Protestant peasants.

He returned to Arnsburg in 1634 but the fighting continued and at one point only the abbot and a lay brother remained, with both of them living in hiding.

Abbot and monks lived a life resembling that of contemporary secular nobles rather than adhering to the Cistercian rules.

Under abbot Robert I Kolb (1673–1701) the damage of the Thirty Years' War was finally overcome and the most crass violations of the order's rules ended.

This was reflected in the pomp of the Baroque reconstruction that created abbey buildings and outposts among its properties that resembled secular palaces and manor houses.

Like many others, its properties were awarded to secular princes who had lost territory west of the Rhine to French expansion, in this case the House of Solms.

It was decided to build the cemetery in the area of the former cloister after the then owner, Georg Friedrich Graf zu Solms-Laubach gave the permission.

There are also 81 women and 6 men – Germans, Luxemburgers, French, Soviets and Polish – who had been shot by the SS at Hirzenhain shortly before the arrival of the U.S. troops.

The main entry into the abbey is by the Baroque Pfortenbau (1770s) giving access to the outer yard with the economy buildings (barn, water mill, brewery and stables).

The war cemetery now occupies the cloister, where rows of graves are interspersed with crosses made of Basaltic tuff.

With the vestibule to the west and a cycle of eleven chapels at its eastern end the church in total measured over 85 meters in length.

[9] For decades, the Gartenhaus has been home of the Dowager Countess Madeleine, a daughter of Gustav Albrecht, 5th Prince of Sayn-Wittgenstein-Berleburg.