The Battle of Prague, which occurred between 25 July and 1 November 1648 was the last action of the Thirty Years' War. While the negotiations for the Peace of Westphalia were proceeding, Sweden took the opportunity to mount one last campaign into Bohemia. The main result, and probably the main aim, was to loot the fabulous art collection assembled in Prague Castle by Rudolf II, Holy Roman Emperor (1552–1612), the pick of which was taken down the Elbe in barges and shipped to Sweden.