In October 1808, Slade was sent to Corunna in command of a hussar brigade. He led the 10th Hussars in the successful cavalry action at Sahagún on 20 December. The 10th arrived too late to play an active role in the action, primarily because Slade insisted on making a stirring, and apparently over-long, speech ending in the words: "... blood and slaughter, march!" Slade made an enemy of Henry, Lord Paget, who commanded all the cavalry in the Corunna campaign. Paget made no pretence of hiding his low opinion of Slade, once calling him "... that damned stupid fellow", in a voice that many nearby officers and troopers heard. Slade shared in the arduous work of the cavalry during John Moore's retreat, and served as a volunteer at the Battle of Corunna, when the cavalry had embarked.