Eugène Charles Catalan was a Belgian mathematician born on May 30, 1814, in Brussels. He is best known for his contributions to number theory and combinatorics. Catalan's work included the study of Catalan numbers, which are a sequence of natural numbers that have many applications in combinatorial mathematics. Catalan also made significant advancements in the field of algebra and geometry. He was a member of the Royal Academy of Science, Letters and Fine Arts of Belgium and contributed to various mathematical journals. His legacy continues to influence modern mathematics, particularly in areas related to combinatorial structures.