Countess Adelaide of Cleves was a noblewoman born in 1418, known for her connections to various European royal families. She was the daughter of John I, Duke of Cleves and Mathilde of Bavaria, which placed her in the midst of significant political alliances during her lifetime. Adelaide married William IV, Duke of Bavaria in 1435, strengthening ties between the Duchy of Cleves and Bavaria. She became the mother of several children, including Albert III, Duke of Bavaria, who continued the family's legacy. Adelaide passed away in 1475, leaving behind a notable lineage.