What was the weather condition the night before the Battle of Waterloo?

The night before the Battle of Waterloo brought heavy rain, leaving the battlefield soaked and the roads difficult to use. The downpour affected both armies’ camps and helped shape Napoleon’s decisions on the following morning.

Waterloo was fought on 18 June 1815 after the armies had spent the night in exposed bivouacs. Rain fell with thunder and lightning, making conditions uncomfortable for the soldiers and turning the ground muddy. The wet roads also slowed the movement of Prussian troops marching from Wavre toward Wellington’s position.

Napoleon delayed the opening of his attack until the ground had dried somewhat. Mud would have made it harder for artillery to move and reduced the effectiveness of cavalry operations. This delay was important because it gave more time for the Prussians to approach the battlefield and support Wellington.

The rain did not decide the battle by itself, but it influenced timing, logistics and tactics. A common mistake is to remember Waterloo simply as a sunny battlefield; the famous fighting took place after a wet night that had already altered the armies’ plans.