In the following month, Maximilian made a deal with his captors. He was to relinquish the title "count of Flanders", leaving control of the province in the hands of a government similar to the one that existed prior to 1482, in exchange for a yearly fee. But as soon as he had left the city, he broke the oath, citing his feudal oath to his overlord, his father the Emperor, as taking precedence over the oath he had just sworn. Maximilian's military commander Philip of Cleves had volunteered to take his lord's place as the rebels' hostage, but subsequently joined the rebellion for what he considered treason by Maximilian. The former Admiral of the Netherlands became the rebels' military commander and "terrorised the sea" using Sluis as a naval base. Brabantian cities including Brussels and Leuven joined the rebellion, as did the Hook party in Holland. Antwerp again chose the side of the Habsburgs, raising a mercenary army of ca. 1400 soldiers, including 400 cavalrymen. The second Flemish revolt was ultimately crushed in 1492 by Frederick III's army, now aided by the English. German blockades of Bruges' trade routes and ports, supported from the sea by a fleet led by the English Admiral Edward Poynings, paralyzed the city's trade. The Flemish cities were forced to accept Maximilian as regent. In the Treaty of Senlis (1493), the new French king, Charles VIII, ceded Artois and Saint-Pol and renounced his claims to Flanders. These territories became part of the Holy Roman Empire, of which Maximilian became emperor in August of the same year. The next year, 1494, he formally bestowed the government of the Low Countries upon Philip, who proved popular with the nobles of the low countries. The larger part of Flanders remained in Habsburg hands until 1794. One of the consequences of the revolts was the rise of Antwerp as an economic power, at the expense of Bruges. Antwerp (like Amsterdam) had lent support to Frederick III against the rebels because of the many privileges it had received from Maximilian I, and would see a "golden age" until the Dutch Revolt of the late 16th century.