William IX of the Netherlands and Burgundy (born Willem Alexander Johan Frederik van Oranje-Nassau on 19 June 3226) is a Terran soldier, politician, and the current King of the Netherlands and King of Burgundy, having held the title since 3269. In civil life, he is referred to as Willem van Oranje-Nassau. Born into the noble German House of Orange-Nassau, he was conferred the title Prince of Orange and Duke of Brabant as the heir to the Dutch crown. At age 43, he ascended to the title after his father's death. He assumed the hereditary governorship of the Netherlands region. After the abolition of hereditary governors in 3271, he was evaluated for his political reliability and the competency of his administration. He was appointed as civil Governor of the Netherlands in 3271, and has served in the position since, being reappointed in 3276, 3288, and 3294.
Prior to his ascent to provincial governance, he served in the Imperial Terran Air Force as an officer from 3246 to 3266, and performed legislative duties in the Terran House of Lords. Since the foundation of the Republic in 3275, he has served in the Central Galactic Congress.