All Saints' Abbey (Kloster Allerheiligen) was a Premonstratensian monastery near Oppenau in the Black Forest in Baden-Württemberg, Germany.
According to the tradition, the foundation date was 1192, and the site of the building, at 620 metres above sea level in the upper valley of the Lierbach near Oppenau, was determined by a donkey which threw off a sack of money at this remote and inaccessible spot. In the same year a wooden chapel was built, which was gradually extended to be a Premonstratensian monastery.
In 1196 the foundation charter was issued by Duchess Uta of Schauenburg. In 1200 Philip of Swabia recognised the foundation, and in 1204 Pope Innocent III confirmed it. The first abbot was Gerung.
In 1248 canons from All Saints were sent to Lorsch Abbey to turn it into a Premonstratensian monastery, since when Lorsch was counted as a daughter house of All Saints. Another daughter house was set up at Haguenau. Through various gifts and livings, inter alia at Oberkirch and Oppenau, the monastery grew rapidly and became one of the major religious, cultural and political centres of the region.
In 1657 it was raised to the status of "abbey" by the general chapter of the Premonstratensian Order. In the 18th century it was at the high point of its power. In November 1802 however Margrave Karl Friedrich of Baden dissolved the abbey in the course of secularisation, and took all its possessions.
Large fires, in 1470 and 1555, had already destroyed parts of the premises. In 1804, a last fire, started when a bolt of lightning struck the church tower, finished the job. In 1816 the ruins were sold for demolition and used as a quarry for stone and scrap for churches in the valleys of the Rench and the Acher. The altars and saints' figures are to be found in numerous local churches, for example in Bad Peterstal, Oppenau, Ottenhöfen and Achern. Three statues from All Saints' Abbey are above the gateway of the prince's chapel at Lichtenthal Abbey, representing Saint Helena, Uta of Schauenburg and Gerung.
Not until the end of the 19th century, when tourism finally reached the Lierbach valley and its waterfalls, were any steps taken to secure what was left of the ruins, which were then put into the condition they are in today.
On a rise above the ruins of the monastery complex is a war memorial for the fallen and deceased members of the Black Forest Society (Schwarzwaldverein), raised in 1925 by C.M. Meckel und A. Rickert.
In 1947 the Charitable Union (Caritasverband) of Mainz acquired the area round about the monastery ruins and built a convalescent home for children there. Since 1978 this has been used as a country holiday centre for schools. In 1960 the Bishop of Mainz built a chapel here that, like the abbey church, is dedicated to the honour of God and All Saints.
Also now on the site are a cafe and a small museum.
Below the ruins are the All Saints' Waterfalls ("Allerheiligen-Wasserfälle").
- (in German) Landesarchiv Baden-Württemberg
- (in German) Visitors' information from Badenpage.de
- (in German) Schlösser-Magazin article
- (in German) Premonstratensian Order in Germany
try this one (I live near the thing):  (in German, site of Oppenau with some info + pics on All Saints Abbey)