In the past the prosperity of Dubrovnik has always been based on maritime trade. Republic of Dubrovnik in the Middle Ages has become the only city-state on the eastern Adriatic coast. In those times Dubrovnik has competed with the Venetian Republic. In addition to its wealth and diplomacy, the city has achieved huge development, especially during the 15th and 16th centuries. The city was one of the most important centers for development of Croatian language and literature. The city wa also a birth place of many important Croatian poets, dramatists, painters, mathematicians, physicists and others.