You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Martin_Luther

Context:
Despite the disagreements on the Eucharist, the Marburg Colloquy paved the way for the signing in 1530 of the Augsburg Confession, and for the formation of the Schmalkaldic League the following year by leading Protestant nobles such as John of Saxony, Philip of Hesse, and George, Margrave of Brandenburg-Ansbach. The Swiss cities, however, did not sign these agreements.

Question:
What ruler, besides John of Saxony and Philip of Hesse, formed the Schmalkaldic League?

George, Margrave of Brandenburg-Ansbach