General Sir James Dawes Douglas GCB (14 January 1785 – 6 March 1862) was a British Army officer, who had a long and illustrious military career, which included commanding Portuguese troops in the Peninsular War.

He entered the army as an ensign in the 42nd regiment, or Black Watch, and was at once taken on the staff of Major-general Sir James Duff, commanding at Limerick, where he became an intimate friend of his fellow aide-de-camp, William Napier.

He was promoted captain in 1804, and, being pronounced fit for a staff situation, was appointed deputy-assistant quartermaster-general with the force sent to South America in 1806.

He advanced into Spain with Sir John Moore, and served with the 2nd division through the retreat from Salamanca and at the Battle of Corunna.

At the battle of Busaco this brigade had to bear the brunt of the French attack, and Douglas's Portuguese received praise for its conduct, mentioned in Lord Wellington's despatch.