Saxe-Eisenach was a historical principality in Germany, part of the larger region of Thuringia. It existed from the early 16th century until the early 19th century, when it was incorporated into the Grand Duchy of Saxe-Weimar-Eisenach. The capital city was Eisenach, known for its rich cultural heritage and historical significance. The principality was notable for its connections to the Lutheran Reformation, as Martin Luther spent time in Eisenach. Additionally, it is famous for the Wartburg Castle, where Luther translated the New Testament into German. Saxe-Eisenach played a role in the political and cultural landscape of central Germany during its existence.