Johann Adolf I was a German nobleman born in 1585, known for being the Duke of Saxe-Weissenfels. He ruled from 1638 until his death in 1668. His reign was marked by efforts to stabilize his duchy during the tumultuous period of the Thirty Years' War, which affected much of Europe. As a member of the House of Wettin, Johann Adolf I was part of a prominent family that played a significant role in the history of Saxony. He is remembered for his contributions to the cultural and political landscape of his time, including the promotion of arts and education within his territory.