Background
He was the son of a Saxon lieutenant General, Gottlob Bernhard.
He was the son of a Saxon lieutenant General, Gottlob Bernhard.
He joined at the age of 13 years in the Saxon army, as a Unterleutnant, in the "Kurfürst" Infantry Regiment. He participated in the campaigns of 1796 to 1812, including the Battle of Saalfeld. Notably, in the n Campaign in 1812, he was head of the General Staff of the VII (Saxon) Corps.
After the return of the Saxon Corps from, the King appointed him Adjutant-General.
In 1813 he negotiated a treaty for mutual defence with Austria. But after the Battle of Lützen (1813), the king of returned to the French fold at Dresden.
Langenau resigned and fought for Austria. On 27 July 1813, Langenau was Major General to the General Staff.
At Dresden, 26 August 1813, he was successful taking command from the wounded Major General v.
Frierenberger. In Leipzig, 16 October 1813, Feldm. Director-Lieutenant Reisner gave direction to Langerau of the Center and the left wing batteries, united at two points, and silenced the enemy guns.
Langerau commanded artillery in battles near Hochheim (on 9 November 1813).
Joseph Radetzky von Radetz served under him in 1814. Langernau in 1817, became a Brigadier General in Linz. In 1827 he was appointed Feldmarschall-Lieutenant and assumed command in Frankfurt.
In 1835, he was appointed General in command, Illyria, Tyrol and intraday Austria, in which position he died at Gratz, Austria.
He was Austrian Plenipotentiary, and the Chairman of the Military Central Commission of the German Federal Assembly at Frankfurt am Main, from November 1818 to 1829.