Duke Albert IV, also known as Albert the Wise, was a prominent nobleman from the House of Habsburg in the late 15th century. He ruled as the Duke of Austria from 1404 until his death in 1439. Albert IV is known for his efforts to strengthen the Habsburg influence in the region and for his role in various political alliances. During his reign, Albert IV focused on consolidating power and expanding his territories. He was involved in several military campaigns and diplomatic negotiations, which helped to enhance the prestige of the Habsburg dynasty. His leadership contributed to the stability and growth of the Austrian lands during a tumultuous period in European history.