Siege of Derry The Siege of Derry ( ) lasted from 18 April to 28 July 1689 , during the Williamite War in Ireland . The city , a Williamite stronghold , was besieged by a Jacobite army until it was relieved by Royal Navy ships . The siege is commemorated yearly in August by the Apprentice Boys of Derry . Background . In the " Glorious Revolution " of 1688 , James II ( King of England , Ireland and Scotland ) , a Roman Catholic convert , was ousted from power by his Protestant daughter Mary and her husband William of Orange . Most of the Irish population were Catholic , and James had given them some real concessions during his reign . He had made an Irish Catholic the Lord Deputy of Ireland ( Richard Talbot ) , and re - admitted Catholics into the Irish Parliament , public office , and the army . Irish Catholics also hoped that James would re - grant them their lands , which had been seized after the Cromwellian conquest of Ireland ( 1649 – 53 ) . James thus looked to Ireland to muster support in re - gaining his kingdoms . Richard Talbot , who was acting as James ' s viceroy in Ireland , was eager to ensure that all strongholds in the country were held by garrisons loyal to James . He focused on the northern province of Ulster , which had been the most heavily planted by British Protestant colonists . By November 1688 , Enniskillen and Derry were the two garrisons in Ulster that were not wholly loyal to James . The elderly Alexander MacDonnell , 3rd Earl of Antrim , was ordered to replace them with a more trustworthy force . He agreed , but wasted several weeks searching for men who were at least six feet tall . A force of about 1 , 200 Scottish Catholic " Redshanks " then set out for Derry . On 7 December , with the army a short distance away , thirteen apprentice boys seized the city keys and locked the gates . On 10 December , King James fled London . He was caught , but fled a second time on 23 December and made his way to France . James ' s first cousin , King Louis XIV of France , said he would help James regain power . In London on 13 February 1689 , William and Mary were crowned . On 12 March , James landed in Kinsale ( on Ireland ' s south coast ) with 6000 French soldiers . He took Dublin and marched north with an army of Irish and French Catholics . The siege . The Derry City Governor , Lieutenant Colonel Robert Lundy , wrote on 15 April that " without an immediate supply of money and provisions this place must fall very soon into the enemy ' s hands " . Lundy called a meeting with several of his most loyal supporters to discuss surrender . News of the meeting spread , angering many of the citizens . That night , Lundy ( in disguise ) and many others left the city and took ship to Scotland . The city ' s defence was overseen by Major Henry Baker , Colonel Adam Murray , and Major George Walker ( also an Anglican priest ) . Their slogan was " No Surrender " . As the Jacobite army neared , all the buildings outside the city walls were set alight by the defenders to prevent them being used as cover by the besiegers . The Jacobite army reached Derry on 18 April . King James rode to Bishop ' s Gate and asked the city to surrender . He was rebuffed , and some of the city ' s defenders fired at him . James would ask thrice more , but was refused each time . This marked the beginning of the siege . Cannon and mortar fire were exchanged , and disease took hold within the city . James returned to Dublin and left his forces under the command of Richard Hamilton . Royal Navy warships under Admiral Rooke arrived in Lough Foyle on 11 June , but refused to smash through the defensive boom ( floating barrier ) across the River Foyle at Culmore . On 28 July , under the orders of Major General Percy Kirke , three armed merchant ships , " Mountjoy " , " Phoenix " and " Jerusalem " ( a cutter ) sailed toward the boom , protected by the frigate HMS " Dartmouth " under Captain John Leake . " Mountjoy " rammed but did not break the boom . Instead , she was broken by sailors in a long boat from the frigate HMS " Swallow " , letting the fleet sail upriver and relieve the city . The city had endured 105 days of siege during which some 8000 people of a population of 30 , 000 were said to have died . Remembrance . The siege is commemorated yearly by the Protestant Apprentice Boys of Derry who stage the week - long Maiden City Festival culminating in a parade around the walls of the city by local members , followed by a parade of the city by the full Association . Although violence has attended these parades in the past , those in recent years have been largely peaceful . The song Derry ' s Walls was written to commemorate the siege .