Ernst Rüdiger von Starhemberg fought in the 1660s under Imperial Lieutenant general Raimondo Montecuccoli against French and Ottoman forces.

On 15 July 1683 Starhemberg refused an offer by the Turkish commander Kara Mustafa Pasha to capitulate, counting on the speedy arrival of an Imperial army, sent by the Habsburg emperor Leopold I who had fled his residence, and the strength of city walls which had been fortified after the first Ottoman Siege of Vienna in 1529.

When after two months the relief army under the command of Polish king Jan Sobieski arrived in the first half of September, Vienna was on the brink of collapse.

Going after the retiring Ottoman troops, Starhemberg was severely wounded in 1686 during the Siege of Buda by a shot in his left hand and had to abandon his command.

After the death of his first wife, he married again in 1689 to Countess Maria Josepha Jörger von Tollet (1668–1746), his fourth cousin, once removed.