Born in Esztergom (Gran), Hungary in 1738, Ott joined "Andlau" Infantry Regiment # 57 as a Fahnrich (cadet) in 1757. He was a veteran of the Seven Years' War, having fought at the battles of Landshut and Liegnitz, being wounded in the latter action. In the War of the Bavarian Succession he served in the "Kálnoky" Hussar Regiment # 2 as a Major. While still serving with the "Kálnoky" Hussars as the Oberst-Leutnant, he led his horsemen in numerous actions during the Austro-Turkish War (1787-1791). After directing the hussars in a successful action at Valje Muliere, he earned promotion to Oberst (colonel) of the regiment. He was awarded the Military Order of Maria Theresa for an action against the Turks at Calafat, Wallachia in modern Romania. In 1791, he was elevated to the noble rank of Freiherr.