He was thus the natural leader of his co-religionists after Victor Amadeus II of Savoy expelled them (1686) from their valleys, and most probably visited Holland; William of Orange, the ruler of that province, certainly gave him help and money. Arnaud occupied himself with organizing his 3,000 countrymen who had taken refuge in Switzerland, and who twice (1687–1688) attempted to regain their homes. The English revolution of 1688, and the election of William to the throne, encouraged the Waldensians to make yet another attempt. Furnished with detailed instructions from the veteran Joshua Janavel (prevented by age from taking part in the expedition) Arnaud, with about 1,000 followers, started in 17 August 1689 from near Nyon on Lake Geneva for their return. On the 27 August, the band, after many hardships and dangers, reached the Valley of St Martin, having passed by Sallanches and crossed many cols and passes reaching up to 9085 ft. They soon took refuge in the lofty and secure rocky citadel of the Balsille, where they were besieged from 24 October 1689 to 14 May 1690 by the troops (about 4,000 in number) of the King of France and the Duke of Savoy.