Which French commander led I Corps in the Waterloo campaign?

D’Erlon led the French I Corps in the Waterloo campaign. His full name was Jean-Baptiste Drouet, comte d’Erlon, a veteran general who commanded one of Napoleon’s principal infantry corps during the Hundred Days of 1815.

D’Erlon’s I Corps was initially positioned between Lille and Valenciennes before Napoleon’s invasion of Belgium. During the campaign it operated with the French left wing under Marshal Ney. At Waterloo, the corps attacked the Allied centre-left in the afternoon, advancing in dense formations toward the area around La Haye Sainte and the ridge held by Wellington’s army.

The attack made serious progress but was disrupted by an unexpectedly powerful charge from the British Union Brigade. The Royal Dragoons, Inniskilling Dragoons and Scots Greys struck the French formations, helping to shatter the assault. D’Erlon is often confused with Reille, who commanded French II Corps, or Lobau, who commanded VI Corps; Kellermann was primarily associated with the French cavalry reserve rather than I Corps.