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Serving for 20 years, from 1978 to 1998, Johannes Rau held the office of President of North Rhine-Westphalia, Germany's most populous state. His tenure was marked by significant contributions to the state's development, including promoting economic growth, fostering cultural vibrancy, and advocating for social justice. Rau's leadership left a lasting impact on the region, shaping its political landscape and earning him widespread respect and admiration.