Stephen Bocskai or István Bocskai (or Bocskay, (1 January 1557 – 29 December 1606) was a Hungarian Calvinist nobleman, and Prince of Transylvania (1605–06), who was an eager advocate of the Hungarian interests and became the leader of a revolt against the Habsburg Holy Roman Emperor's effort to impose Roman Catholicism on the Kingdom of Hungary, when it was partitioned between the Ottoman Empire and the Habsburg Monarchy. He established an alliance with the Ottoman Empire and, supported by the hajdus, compelled archduke Matthias to reaffirm and guarantee religious freedom for both Royal Hungary and Transylvania concluded by the Treaty of Vienna (1606). As a recognized patron of Protestant Reformation, his statue can be found on the Reformation Wall in Geneva, Switzerland.