Wendish Crusade

When the Second Crusade was called, many south Germans volunteered to crusade in the Holy Land. The north German Saxons were reluctant. They told St Bernard of their desire to campaign against the Slavs at a Reichstag meeting in Frankfurt on 13 March 1147. Approving of the Saxons' plan, Eugenius issued a papal bull known as the Divina dispensatione on 13 April. This bull stated that there was to be no difference between the spiritual rewards of the different crusaders. Those who volunteered to crusade against the Slavs were primarily Danes, Saxons, and Poles, although there were also some Bohemians. The Papal legate, Anselm of Havelberg, was placed in overall command. The campaign itself was led by Saxon families such as the Ascanians, Wettin, and Schauenburgers.

http://en.wikipedia.org/wiki/Second_Crusade