A small eruption of Mount Rinjani, with volcanic lightning. (Oliver Spalt/CC BY 2.0/Wikimedia Commons)

A small eruption of Mount Rinjani, with volcanic lightning. (Oliver Spalt/CC BY 2.0/Wikimedia Commons)

A British scientist thinks a volcanic eruption may have led to Napoleon Bonaparte’s crushing defeat at Waterloo, in what is now Belgium, on June 18, 1815.

Historians say heavy rains fell on Napoleon’s troops the night before the big battle, causing the ground to become very muddy and soggy.

With these miserable conditions, Napoleon’s artillery and soldiers became bogged down and stuck in the mud, forcing him to delay the start of the battle.

Napoleon Bonaparte (1769-1821). Painting by Jacques Louis David (Wikimedia)

Napoleon Bonaparte (1769-1821). Painting by Jacques Louis David (Wikimedia)

This gave his enemies, the allied forces of Great Britain, Germany and the Netherlands, enough time to regroup and develop a battle plan that would defeat one of the most brilliant military leaders in history.

Matthew Genge, from Imperial College, London says he discovered that electrified ash from volcanic eruptions can actually make its way high into Earth’s ionosphere and short-circuit its current.

Just two months before the history-changing battle, Indonesia’s Mt. Tambora violently erupted, killing more than 10,000 people.

Outlining his findings in a study published by the journal Geology, Menge suggests that electrically charged volcanic ash from the devastating eruption short-circuited the ionosphere, which produced the clouds that dumped the soaking rains on Napoleon and his troops at Waterloo.

Aerial view of the caldera of Mt Tambora at the island of Sumbawa, Indonesia. (Jialiang Gao/CC BY-SA 3.0/Wikimedia Commons)

Aerial view of the caldera of Mt Tambora at the island of Sumbawa, Indonesia. (Jialiang Gao/CC BY-SA 3.0/Wikimedia Commons)

Historians say Napoleon Bonaparte’s military career took off during the French Revolution (1789-1799).

After a successful coup d’état at the end of the revolution, he seized political power and in 1804 crowned himself Emperor of France.

The stunning loss at Waterloo forced Napoleon to abdicate his throne on June 22, 1815.

He was then exiled to the isolated island of St. Helena, where he died in 1821.