Venice and Genoa were Europe's main gateways to trade with the East, and producers of fine glass, while Florence was a capital of silk, wool, banking, and jewellery. The wealth such business brought to Italy meant that large public and private artistic projects could be commissioned. The republics were heavily involved in the Crusades, providing support and transport, but most especially taking advantage of the political and trading opportunities resulting from these wars. Italy first felt the huge economic changes in Europe which led to the commercial revolution: the Republic of Venice was able to defeat the Byzantine Empire and finance the voyages of Marco Polo to Asia; the first universities were formed in Italian cities, and scholars such as Thomas Aquinas obtained international fame; Frederick of Sicily made Italy the political-cultural centre of a reign that temporarily included the Holy Roman Empire and the Kingdom of Jerusalem; capitalism and banking families emerged in Florence, where Dante and Giotto were active around 1300.