HMS Emerald (1795) dispatched a squadron of five ships, including "Emerald" and commanded by Nelson in the 74-gun , to locate a large invasion fleet that had left Toulon. After receiving intelligence on 22 May, Nelson correctly predicted the French fleet's destination and set course for Alexandria where the British captured or destroyed all but two of the French ships at the Battle of the Nile, which occurred between 1–3 August 1798. "Emerald" missed the battle; having previously become separated from the rest of the squadron in a storm on 21 May, she arrived at Aboukir Bay on 12 August. When Nelson left
Action of 24 June 1801 a British fleet under Rear-Admiral Sir Horatio Nelson destroyed the French Mediterranean Fleet at Aboukir Bay on the Egyptian coast. The battle completely reversed the strategic situation in the Mediterranean: British forces had evacuated the region in 1796 after the Treaty of San Ildefonso brought Spain into the war on the French side, but they were now able to return in large numbers. As French maritime lines of communication were cut, the French "Armée d'Orient" under General Napoleon Bonaparte became trapped in Egypt. Unable to return to Europe by sea, the army attempted and failed to pass overland through Palestine