German Brotherhood of Assassins

The Northern European Assassins were a branch of the Assassin Order, located in the northern part of Europe which included Germany and the Netherlands.

During the early 16th century, the Northern European Assassins were led by the Dutch scholar Desiderius Erasmus. Circa 1512, Erasmus sent a letter to Claudia Auditore da Firenze, the acting leader of the Italian Assassins, warning the Italian branch of the revolutionary religious thoughts of Martin Luther, fearing for more chaos in the European continent.

Source

 * Assassin's Creed: Revelations novel