King John's Castle

History

King John's Castle, also called Limerick Castle, stands along the River Shannon in Limerick, Ireland. The earliest parts of the surviving castle were built in 1212 for John, king of England and Lord of Ireland. The current site of King John's Castle was formerly a Viking fortress on King's Island, established in 922.

The story of Limerick's control shifted in 1169, when the Anglo-Norman invasion of Ireland began in earnest under Richard de Clare (Strongbow), bringing many of Ireland's port cities under Anglo-Norman rule.

By 1172, after a brief agreement between Domnall Mór Ó Briain, king of Thomond, and Henry II of England, an Anglo-Norman garrison was placed at Limerick. However, in 1175, Ó Briain went back on his word and placed the town under siege. Henry II dispatched Raymond le Gros FitzGerald to restore order, leading to the construction of an early ringwork-style castle in the north-eastern corner of today's King John's Castle.

After Richard de Clare's death in 1176, the garrison withdrew, and Ó Briain regained control of Limerick. During this time, the ringworks were destroyed, and the surrounding ditch was filled in.

Ó Briain's death in 1194 opened the door for the Anglo-Normans to retake the area in 1195, now led by John, who had been made Lord of Ireland by his father, Henry II, in 1177. After ascending to the English throne, John ordered fortifications to be built in 1204, including at Dublin, but he did not issue a similar order for Limerick, because a fortification already existed there. In 1212, a considerable amount of money was spent on building work at Limerick, which produced the earliest parts of the surviving castle, including the iconic twin-towered Gatehouse and North-East Tower, marking a new phase of the castle's development.

A figure of King John in the castle exhibition.

With the new castle on the River Shannon, Limerick prospered. King John established a mint inside the castle and appointed Godfrey de Rupe as its administrator. A chapel dedicated to St Andrew was also founded. By King John's death in 1216, the stone twin-towered Gatehouse and North-East Tower had risen, but the remaining outer walls were still earthwork or timber.

Subsequent royal attention continued under Henry III of England, who added two great river towers at each end of the western curtain wall. This section of the wall also included the castle's Water Gate, which is now the only surviving medieval town gate in Limerick. Around this time, the city walls were extended to encompass Limerick Castle, increasing its security against attack.

In 1280, King Edward I ordered the construction of a large two-story hall along the western curtain wall. This hall was demolished in the 18th century, but its undercroft surfaced during 1993-1994 excavations. In the late 13th century, the inner courtyard sloped steeply from the northeast high ground toward the Water Gate. In 1297, laborers leveled the courtyard, producing the even ground visible today.

In early 1317, during the Bruce campaign in Ireland, Edward de Brus, the brother of King Robert the Bruce of Scotland, and his army approached Limerick and reached as far as Castleconnell on the Shannon. They found the city well defended and faced hostile local conditions and famine, and they retreated without taking the castle or the city.

In 1370, Limerick was seized and burned, then reclaimed later that year. In 1423, James FitzGerald, 6th Earl of Desmond, was appointed constable and provided funds for repairs, yet the mayor and council distrusted him and petitioned King Henry VI for control, which they received.

During a visit to Limerick Castle in 1574, a priest named David Wolfe described the castle as “unoccupied for many years, with decaying buildings and walls”.

During Queen Elizabeth's reign, she created the office of Lord President of Munster. This led to new regional fortifications and increased spending on existing strongholds, including Limerick Castle. The earliest surviving maps of the castle and city date to this era.

Between 1579 and 1583, during the rebellion of Gerald FitzJames, 14th Earl of Desmond, the practice of confining prisoners at Limerick Castle was revived, and men of rank were held there as hostages to secure the good behavior of the Irish chieftains. In 1581, John Shereff, clerk of the ordnance and vice-constable of the castle, and his wife were implicated in a successful breakout by prisoners. A contemporary report tells us that the pair “were recompensed for it shortly after, for they both lovingly hanged together!”

In 1611, the Bastion was constructed in the south-east corner of the castle.

In May and June 1642, Limerick Castle experienced its most traumatic period. In the fall of 1641, widespread rebellion began in Ulster. About 600 English Protestant settlers fled the city of Limerick and took refuge in Limerick Castle. The Mayor of Limerick, Dominick Fanning, a Catholic, arranged for a large Catholic army raised in Munster to be admitted within the city walls of Limerick in May 1642. Limerick quickly fell with scarcely a shot fired.

Captain George Courtenay, 1st Baronet of Newcastle of Powderham, and constable of the castle, assumed command of what remained of the garrison and prepared to defend the castle. The Confederate Munster army, led by General Garrett Barry, laid siege to the castle on May 18th, 1642. The besieging forces lacked siege weapons or the firepower to batter the castle walls and resorted to digging timber mines under the foundations of the walls and setting them ablaze. The garrison inside the castle responded by digging countermines, which were meant to intercept incoming miners. These mining activities lasted several weeks. The siege came to a climax when Irish miners collapsed the northern corner of the Bastion, which was quickly followed by the collapse of the southern end of the eastern wall of the castle. George Courtenay surrendered the castle to General Barry on June 23rd, after a siege of 37 days. During the siege, up to 280 people died, and most of them were buried in mass graves in an area of the courtyard, with up to 15 or 16 individuals in each grave. One of these burial pits was uncovered by archaeologists in 1993 at a spot behind the gatehouse, and it held the skeletal remains of 14 women and children. They likely died of dysentery, which broke out in the latter stages of the siege because of poor hygiene and chronic shortages of food and drink. The 1642 Siege of Limerick was the first of five sieges of the city of Limerick in the 17th century.

A cannon on the castle walls.

In 1651, the city was captured by the Parliamentarian army led by Henry Ireton, following a gruelling six-month siege, and the castle was surrendered, with the city, to Cromwell's army. The new administration saw to it that the castle was repaired. Around this time, the tops of the main towers were knocked down and new vaulting was built to support gun platforms at the tops of the towers.

The accession of James II, a Catholic, in 1685 had far-reaching consequences in Limerick, because the Catholic population became predominant. When James landed in Ireland in 1689 to win his crown back from William III, Limerick, including the castle, was secured for him, and there was no repetition of the siege of the castle of 1642. After the surrender of the city following the siege of 1691, further repairs were made to the castle by a Dutch officer named Vander Stam, and they were commemorated in an inscription on the south-western tower.

In 1751, the castle saw its most important addition since the Bastion was built 140 years earlier: a large barracks. The fortuitous timing of this construction became clear in 1760, when work began to dismantle the medieval town walls of Limerick. The barracks gave the castle a new purpose, and it was left intact while the other medieval fortifications in the city were torn down. Without the barracks, the castle might have been demolished as well.

In his History of Limerick of 1787, John Ferrar described the barracks as a "handsome square" of fifty-four apartments, designed to accommodate 400 infantry. Limerick Castle was first referred to as King John's Castle in that book.

In 1793, the barracks were enlarged, resulting in the demolition of the eastern curtain wall and much of the Bastion, creating a generous parade ground opening to Nicholas Street. The old storehouse, originally built as the Great Hall by Edward I, was also levelled.

In May 1922, the British military withdrew from the castle, and custody passed from the Royal Welsh Fusiliers to a Provisional Government force commanded by General Michael Brennan. A few months later, the castle fell into Republican hands, and the barracks were set on fire on July 21st, 1922, before the castle was retaken.

In the 1970s, authorities demolished two of the three remaining barracks buildings due to safety concerns and repaved the courtyard, allowing the Office of Public Works to conduct its first archaeological excavation in 1976.

A restoration plan for the castle as a National Monument was devised in 1988. As part of this plan, all housing added to the courtyard was removed. Excavation revealed the remains of the eastern curtain wall. A new visitor center was constructed above the archaeological excavations on the eastern edge of the courtyard. This design ensures excavation features are both preserved and displayed within the center.

A €5.7 million redevelopment between 2011 and 2013 added new interactive, computer-animated exhibitions and a cafe. In January 2026, the operation of the castle passed from Shannon Heritage to Discover Limerick, a company owned by Limerick City and County Council.

Castle Highlights

King John's Castle ranks among Ireland's largest. It overlooks the River Shannon from King's Island in Limerick. Cross the bridge for a scenic view from the other side. The rectangular inner bailey is encircled by lofty curtain walls and massive round corner towers on three sides, with the square Bastion Tower in the southeast corner.

The twin-towered gatehouse.

The massive Gatehouse is flanked by imposing twin round towers. The North-East Tower features distinctive double-arrow loops, allowing two archers to control the area around the castle.

The visitor center displays preserved excavation work from the 1990s, with the upper floors featuring exhibits that bring to life the castle's medieval history.

The castle across the River Shannon.

Visitors can walk the castle walls and explore the towers and chambers, and the Siege Cafe has views of the castle. In the South West Tower, a display tells a romantic traditional story about Máire Rúa, the wife of Conor O'Brien of County Clare, who refused to make terms with Henry Ireton and is believed to have been assassinated at his order. According to the story, Máire Rúa traveled to Limerick, told Ireton she was Conor's widow, and married one of his officers, a Captain Cooper, which saved the O'Brien property from forfeiture.

You can easily spend half a day at the castle or longer. If you want to try another castle on the same day, Bunratty Castle and Desmond Castle in Adare are less than an hour from Limerick.

King John's Castle is also haunted.