Invasion of Java (1811) - Siege of Fort Cornelis

Siege of Fort Cornelis

Fort Cornelis measured 1 mile (1,600 m) in length by between 600 yards (550 m) and 800 yards (730 m) in breadth. Two hundred and eighty cannon were mounted on its walls and bastions. Its defenders were a mixed bag of Dutch, French and East Indies troops. Most of the locally raised East Indian troops were of doubtful loyalty and effectiveness, although there were some determined artillerymen from Celebes. The captured station at Weltevreeden proved an ideal base from which the British could lay siege to Fort Cornelis. On 14 August the British completed a trail through the forests and pepper plantations to allow them to bring up heavy guns and munitions, and opened siege works on the north side of the Fort. For several days, there were exchanges of fire between the fort and the British batteries, manned mainly by Royal Marines and sailors from HMS Nisus.

A sortie from the fort early on the morning of 22 August briefly seized three of the British batteries, until they were driven back some of the Bengal Sepoys and the 69th Foot. The two sides then exchanged heavy fire, faltering on 23 August, but resuming on 24 August. The Franco-Dutch position worsened when a deserter helped General Rollo Gillespie to capture two of the redoubts by surprise. Gillespie, who was suffering from fever, collapsed, but recovered to storm a third redoubt. The French General Jauffret was taken prisoner. Two Dutch officers, Major Holsman and Major Muller, sacrificed themselves to blow up the redoubt's magazine.

The three redoubts were nevertheless the key to the defence, and their loss demoralised most of Janssens's East Indian troops. Many Dutch troops also defected, repudiating their allegiance to the French. The British stormed the fort at midnight on 25 August, capturing it after a bitter fight. The siege cost the British 630 casualties. The defenders' casualties were heavier, but only those among officers were fully recorded. Forty of them were killed, sixty-three wounded and 230 captured, including two French generals. Nearly 5,000 men were captured, including three general officers, 34 field officers, 70 captains and 150 subaltern officers. 1,000 men were found dead in the fort, with more being killed in the subsequent pursuit. Janssens escaped to Buitenzorg with a few survivors from his army, but was forced to abandon the town when the British approached.

Total British losses in the campaign after the fall of Fort Cornelis amounted to 141 killed, 733 wounded and 13 missing from the Army, and 15 killed, 45 wounded and three missing from the Navy; a total of 156 killed, 788 wounded and 16 missing by 27 August.