Louis of Nassau (January 10, 1538 – April 14, 1574) was the third son of William, Count of Nassau, and Juliana of Stolberg and the younger brother of Prince William of Orange Nassau. Louis was a key figure in the revolt of the Netherlands against Spain, unlike his brother William, he was a strongly convinced Calvinist. He helped his brother in various ways including by arranging the marriage between William and his second wife Anna of Saxony. In 1569 William appointed him governor of the principality of Orange giving him an indisputable position in French politics.
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