He was the eldest son of Count Christian Christoph Clam-Gallas (1771–1838), patron of Beethoven, and Countess Josephine Clary-Aldringen (1777–1828).

In 1848, called to Italy under the orders of General Joseph Radetzky, he commanded a brigade which distinguished itself at Santa Lucia, Vicenza and the Battle of Custoza.

He was decorated with the Military Order of Maria Theresa and promoted to Field Marshal Lieutenant (equivalent of two-star general).

At the beginning of July he was moving into Hungary to Hungarian: Brassó (now Romanian: Braşov), to support Alexander von Lüders on the right flank.

He was relieved of his command and replaced by Count Leopold Gondrecourt in the early morning of 3 July 1866 and thus took no part in the defeat of the Austrian main army at Königgrätz that day.