Timeline of military aviation
26 June 1794 – The French Aerostatic Corps used a tethered balloon at the Battle of Fleurus as a vantage point. 12 July 1849 – In First Italian War of Independence, Austrian forces besieging Venice launched some 200 incendiary balloons, each carrying a 24- to 30-pound bomb that was to be dropped from the balloon with a time fuse over the besieged city.
Source: Wikipedia — Timeline of military aviation (CC BY-SA 4.0)