Johann Adolf, Freiherr von Thielmann (27 April 1765 – 10 October 1824) was a Saxon general who served with Saxony, Prussia and France during the Napoleonic Wars.

After the disaster of Jena,[2] Thielmann was sent by Saxony as ambassador to Napoleon I, became his ardent admirer, and did much to bring about the Franco-Saxon alliance.

[2] In 1809, as colonel of Free-Corps, he opposed the advance of the Austrians into Saxony, and was rewarded for his services with the grade of major-general, further promotion to lieutenant-general following in 1810.

As commander of the Saxon Heavy Cavalry Brigade he took part in the advance on Moscow two years later, and his exceptional bravery at Borodino attracted the attention of Napoleon, who took Thielmann into his own suite.

[2] Early in the following year he became a lieutenant-general in the Prussian service, and in command of the III Corps (with Carl von Clausewitz as his chief of staff) he took part in the Waterloo campaign.