The Battle of Derna was a decisive victory of a combined army of U.S. Marines, Greeks, Turks and Arabs over the forces of the Barbary coast nation of Tripoli during the First Barbary War.
Background
The former Consul to Tunis, William Eaton returned to the Mediterranean with the title of "Naval Agent to the Barbary States in 1804. Eaton had been granted permission from the United States government to back the claim of Hamet Karamanli, the rightful heir to the throne of Tripoli, who had been deposed by his brother Yussif Karamanli. Upon his return Eaton sought out Hamet, who was in exile in Egypt, and made a proposal to reinstate him to the throne. Hamet agreed to Eaton's plan.
The Forces
Commodore Samuel Barron, the new Naval commander in the Mediterranean gave Eaton naval support from the Hero, Nautilus, Hornet and the Argus commanded by Captain Isaac Hull, which were to provide off shore bombardment support. A detachment of U.S. Marines was given to Eaton under the command of Lt. Presley O'Bannon. Eaton and Hull made their base of operations at Alexandria, Egypt, and there with the help of Hamet, recruited about 500 Arab, Greek and Turkish mercenaries. Eaton named himself General and Commander-in-Chief of the combined force.
The Desert Trek
General Eaton now led his army on 600 mile trek across the Libyan desert. Their objective was the port city of Derna, the capitol of the province of Cyrenaica. Supplies and money were promised to the largely mercenary force when they reached the city. During the 50 day trek Eaton became concerned with the relationship between the Christians and the roughly 200 Muslim mercenaries in his force. On several occasions mutiny threatened the success of the expedition. The force finally reached the port city of Bomba in late April, up the coast from Derna, where the Argus, Nautilus and the Hornet along with Captain Hull were waiting. There Eaton and his force received supplies and money to pay the mercenaries.
The Battle
On April 27, two days after arriving at Bomba, Eaton's forces opened fire on Derna. Hull's ships bombed the city's batteries for about an hour. Then at 2:45pm Lt. O'Bannon led U.S. Marines, supported by some of the mercenaries in an attack on the city's harbor fortresses. O'Bannon charged and the defenders fled in such haste that they left their cannon loaded and ready to fire. When O'Bannon captured the batteries he turned the cannon on the city and opened fire. While this attack was going on, Gen. Eaton stormed the castle at Derna. Eaton was seriously wounded in the attack but his force carried the defenses. By 4:00 the entire city had fallen. Captain Hull raised a U.S. flag over the city, the first time a U.S. flag had flown over a fortification that side of the Atlantic. Yusuf was aware of the attack on Derna and had sent reinforcements to the city. They arrived too late as the city had already fallen. Still they dug in and prepared to retake the city. On May 13 they attacked the city. The Argus and Eaton's captured batteries pounded the attackers, and when they reached the city they were repulsed and retreated under continued bombardment. Skirmishing and several other minor and attempts were made on the city in the following weeks but the city remained in American control. From Derna Eaton now planned to march across the desert and attack Tripoli from the land. During his march he was informed of the treaty signed between Tobias Lear and Yusuf Karamanli. In the middle of his trek Eaton was ordered to return to Egypt with Hamet.
Aftermath
The Battle of Derna was the first recorded land battle of the United States on foreign soil. The battle was the decisive action of the First Barbary War, although Eaton was angered by what he called a 'sell-out' between Consul Lear and the bey. Hamet was returned to Egypt and Eaton's mercenaries were never fully paid. William Eaton returned to the United States as a national hero. The attack on the city is forever remembered as it was the inspiration for the lyrics to the Marine Hymn "to the shores of Tripoli". Hamet was so impressed by Presley O'Bannon and his attack on the city, the he presented O'Bannon with his own Mameluke sword.