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The Union of Lublin, painted by Jan Matejko, symbolizes the unification of the Crown of the Kingdom of Poland and the Grand Duchy of Lithuania into a single, powerful entity known as the Polish-Lithuanian Commonwealth. This historic event, depicted in Matejko's artwork, marked a significant milestone in Eastern European history, consolidating the two nations' political, economic, and cultural spheres and shaping the region's geopolitical landscape for centuries to come.