The not so easily accessible lagoon island became the government seat of the Venetian Sea-League in 811. The independent city state was founded in the 11th century under the leadership of a ‘Doge’ and guided by the ‘Council of Wise Men’. Around 1000, Venice began to subjugate the coastal cities of Istria and Dalmatia in the interest of controlling more and more of the trade with the Orient. During the crusades, its colonial empire extended over the entire Balkan Peninsula to Asia Minor. In the 15th century Venice had 200,000 inhabitants and a large fleet of trading vessels and war ships. The beginning of the decline in importance of Venice as a major harbor city coincided with the discovery of America.