He is known for his career in Habsburg Spain, as Viceroy of Catalonia (1698–1701), head of the Austrian army in the War of the Spanish Succession (1701–1705) and governor of Gibraltar in 1704.

In 1695 he was sent by the Emperor to Spain at the head of an army-unit of 2,000 German soldiers to help defend Catalonia against superior French army and navy forces.

After the start of the War of the Spanish Succession he was appointed the head of the Austrian troops supporting Archduke Charles's cause in Spain.

This proved false and the fleet returned to Lisbon after a brush with French naval forces heading to Toulon.

[1] Following the arrival of Allied reinforcements and supplies, enabling Prince George to take the offensive, the siege was abandoned in April 1705.

He left Gibraltar and took command of the conquest of Barcelona and was killed on 13 September, storming the citadel of Montjuich.