Johann Baron von Hiller was an Austrian general during the French Revolutionary Wars and the Napoleonic Wars. He held an important command during the 1809 campaign against France, playing a prominent role at the Battle of Aspern-Essling.

In the Battle of Aspern-Essling, Napoleon crossed the Danube near Vienna, but the French and their allies were attacked and forced back across the river by the Austrians under Archduke Charles. It was the first time Napoleon had been personally defeated in a major battle, as well as his first battle defeat in 10 years since the Siege of Acre, and his first battle defeat as head of state.