Windsor Castle was built by William the Conqueror, who reigned from 1066 until his death in 1087. His original wooden castle stood on the motte of the present Round Tower ("A" on the castle plan).
The castle formed part of his defensive ring of castles surrounding London.
Early in William's reign he had taken possession of a manor in what today is Old Windsor, probably a Saxon royal residence. Between 1070 and 1086, he leased the site of the present castle from the Manor of Clewer and built the first motte-and-bailey castle.
At this time the castle was defended by a wooden palisade. The original plan of William the Conqueror's castle is unknown. His successor William II is thought to have improved and enlarged the structure, but the Conqueror's youngest son King Henry I was the first sovereign to live within the castle.
Concerned for his own safety due to the instabilities of his reign, he took up residence there and celebrated Whitsuntide at the castle in 1110. His marriage took place in the castle in 1121.
The earliest surviving buildings at Windsor date from the reign of Henry II who came to the throne in 1154. He replaced the wooden palisade surrounding the old fortress with a stone wall interspersed with square towers; a much-altered part of this defensive wall can be seen on what is today the east terrace. Henry II also built the first stone keep on the motte at the centre of the castle.
In 1214, the castle was besieged during the revolt of the English barons against Prince John. The King's Welsh troops took flight, and the Prince escaped to France. Later in 1215 at Runnymede, close to the castle, John, now King, was forced to seal Magna Carta. In 1216, during the First Barons' War, the castle was again besieged, but this time withheld despite damage to the structure of the lower ward.
This damage was repaired in 1216 by John's successor King Henry III, who further strengthened the defences with the construction of the western curtain wall, much of which survives today. The oldest existing parts of the castle include the curfew tower ("T"), constructed in 1227.
Henry III died in 1272, and there seems to have been little further building carried out at the castle until the reign of King Edward III (1327–1377).
King Edward III was born in the castle on 13 November 1312, and was often referred to as "Edward of Windsor". Beginning in 1350, he initiated a 24-year rebuilding program by demolishing the existing castle, with the exception of the Curfew Tower and some other minor outworks. Henry II's keep was replaced by the present keep (the Round Tower), although it was not raised to its present height until the 19th century. The castle's chapel was substantially enlarged. Also dating from this time is the Norman Gate ("M"). This large and imposing gate at the foot of the Round Tower.
In 1348 King Edward III established the Order of the Garter, whose annual ceremony still takes place in St George's Chapel, the principal chapel of the castle. In 1353–1354, he had the Aerary Porch built.
Between 1350 and 1377, Edward III spent £51,000 on renovating Windsor Castle; this was the largest amount spent by an English medieval monarch on a single building operation. This sum is impressive as Windsor Castle was already a substantial building before Edward began expanding it.
In 1390, during the reign of Richard II, it was found that St George's chapel was close to collapse, and a restoration process was undertaken. The clerk of the works was one of King Richard's favourites, Geoffrey Chaucer, who served as a diplomat and Clerk of The King's Works. Whatever his skills as a surveyor and builder were, within 50 years of his restoration the chapel was again ruinous.
King Edward IV (1461–1483), the first King from the House of York, began construction of the present St. George's Chapel in 1475. Construction of the chapel marked a turning point in the architecture of the castle. The more stable political climate following the end of the Wars of the Roses meant that future building tended to be more considerate of comfort and style than of fortification. The castle's role changed from that of royal bastion to that of a royal palace. One example of this is the "Horseshoe Cloister" from 1480, built near the chapel to house its clergy.
Edward III was the monarch who began the transformation of the castle from a fortress to a comfortable residence. Compared to royal palaces at Whitehall and Nonsuch, Windsor was still a bleak residence.
Henry VIII (who reigned from 1509–1547) rebuilt the principal castle gateway in about 1510, siting it in such a place that, should the gateway fall in an attack, further invasion into the castle would involve an uphill battle. The coat of arms above the arch and portcullis bears the pomegranate badge of the king's first queen, Catherine of Aragon. Even after Henry, the castle was still not a comfortable residence. His successor and son,King Edward VI (who reigned from 1547–1553) still a boy, wrote while staying in the castle "Methink I am in a prison, here are no galleries, nor no gardens to walk in."
Edward VI's sister Queen Elizabeth I (who reigned 1558–1603) spent much of her time at Windsor and regarded it as the safest place in her realm and would retire there in moments of anxiety "knowing it could stand a siege if need be". While her statement suggests the castle was still very much a fortress, she too contributed to the transformation by constructing the north terrace ("N").. At the outbreak of Bubonic plague in London, Elizabeth I and her court left for Windsor Castle in 1563 and discouraged anyone else from following. She had a gallows erected ordering anyone visiting from London to be executed.
Elizabeth I was followed by James I, and he by his son Charles I, neither of whom made significant changes to the castle. During the English Civil War, the castle fell to the Roundheads soon after the outbreak of hostilities. Prince Rupert of the Rhine arrived to retake the town and castle a few days later but was unable to retake it. Windsor Castle became the headquarters of Oliver Cromwell's New Model Army. The garrison stationed there was underpaid and looted the castle's treasures. Later during the Commonwealth there were squatters in the castle. Asone source put it “The King's house was a wreck; the fanatic, the pilferer, and the squatter, having been at work ... Paupers had squatted in many of the towers and cabinets”.
For the duration of the Commonwealth and the Protectorate, the castle remained a military headquarters, and a prison for more important captured Royalists. For a short time, King Charles was kept under arrest in the castle, and after his execution in January 1649, his body was smuggled back to Windsor in the dead of night through a snowstorm to be interred without ceremony in the vault beneath the choir in St George's Chapel, next to the coffins of Henry VIII and his wife Jane Seymour.
The Restoration of the monarchy in 1660 was to prove the first period of significant change to Windsor Castle for many years. Charles II did much to restore and refurnish the castle after the damage suffered during the civil war.
Charles II laid out the avenue known as the Long Walk It was not the only part of Windsor to be inspired by Versailles. Charles II commissioned the architect Hugh May to rebuild the Royal Apartments and St George's Hall. May replaced the original Plantagenet apartments on the north terrace with the cube-like Star Building. The interiors of these new apartments were decorated with ceilings by Antonio Verrio and carving by Grinling Gibbons. The King also acquired tapestries and paintings to furnish the rooms. These artworks were to form the core of what was to become known as the Royal Collection. Three of these rooms survive relatively unchanged: the Queen's Presence Chamber and the Queen's Audience Chamber, both designed for Charles II's wife Catherine of Braganza, and the King's Dining Room. These retain both their Verrio ceilings and Gibbons' panelling. Originally there were twenty rooms in this style. Some of Gibbons' carvings were rescued at various times when alterations were being made, and in the 19th century these carvings were incorporated into new interior design themes in the Garter Throne Room and the Waterloo Chamber.
Following the death of Charles II in 1685, the Castle fell into a state of neglect. While the precincts and park remained a complex of inhabited royal mansions, sovereigns themselves preferred to live elsewhere.
During the reign of William and Mary (1689–1702), Hampton Court Palace was enlarged and transformed into a huge modern palace. Later Queen Anne preferred to live in a small house close to the walls of the castle.
It was not until 1804 that King George III, the father of 15 children, needing a larger residence,moved back into the castle. Work carried out by Charles II had been on the contemporary, more classical, style of architecture popular at the time. Inigo Jones had introduced Palladianism to England during the time of Charles I but George III felt this style was not in keeping with an ancient castle, and had many of Charles II's windows redesigned and given a pointed Gothic arch, so the castle began once again to acquire a medieval appearance. Windsor Castle was once again to become a place of royal confinement. In 1811 King George III became permanently deranged and was confined to the castle for his own safety. During the last nine years of his life he seldom left his apartments at Windsor.
It was during the reign of King George IV between 1820–1830 that the castle was to undergo the greatest single transformation in its history. George IV, known for his extravagant building at both Carlton House and the Royal Pavilion during his regency, now persuaded Parliament to vote him £300,000 for restoration. The architect Jeffry Wyatville was selected, and work commenced in 1824. The work took twelve years to complete and included a complete remodelling of the Upper Ward ("B"), private apartments ("D"), Round Tower ("A"), and the exterior facade of the South Wing ("E") which gave the castle its near symmetrical facade seen from the Long Walk.
Wyatville was the first architect to view the castle as one composition, rather than a collection of buildings of various ages and in differing styles. As an architect he had a preference for imposing symmetry, whereas the castle which had evolved piecemeal over the previous centuries had no symmetry at all. Wyatville imposed a symmetry of sorts on the existing buildings of the Upper Ward, by raising the heights of certain towers to match others, and refacing the Upper Ward in a Gothic style complete with castellated battlements to match the medieval buildings, including St George's Chapel in the Lower Ward.
Much of the interior of the Castle was given the same treatment as the exterior. Many of the Charles II state rooms which remained after George III's redecorations were redesigned in the Gothic style, most notably St George's Hall , which was doubled in length. Wyatville also roofed over a courtyard to create the Waterloo Chamber. This vast hall lit by a clerestory was designed to celebrate the victors of the Battle of Waterloo and was hung with portraits of the allied sovereigns and commanders who vanquished Napoleon. A large dining table at the centre of the chamber seats 150 people. Work was unfinished at the time of George IV's death in 1830, but was virtually completed by Wyatville's death in 1840.
Queen Victoria and Prince Albert made Windsor Castle their principal royal residence. Many of their changes were to the surrounding parklands rather than the buildings. In particular, the "Windsor Castle and Town Approaches Act", passed by Parliament in 1848, permitted the closing and re-routing of the old roads which previously ran through the park from Windsor to Datchet and Old Windsor. These changes allowed the Royal Family to undertake the enclosure of a large area of parkland to form the private " Home Park" with no public roads passing through it.
Queen Victoria had retreated to Osborne House on the Isle of Wight for privacy following the death in 1861 of Prince Albert in the Blue Room at Windsor Castle. Albert was buried in the Royal Mausoleum built at nearby Frogmore, within the Home Park of the Castle (and eventually Victoria was buried beside him).
From Albert's death until her own death in 1901, Windsor Castle was one of Victoria's main homes, and she seldom visited Buckingham Palace again. Her retreat into the privacy of the castle after the death of Prince Albert acquired her the soubriquet "The Widow of Windsor". The prince's rooms were maintained exactly as they had been at the moment of his death, but this did not prevent improvements and restoration from taking place.
In 1866 Anthony Salvin created the Grand Staircase in the State Apartments ("C"). This great stone staircase in the Gothic style rises to a double height hall lit by a vaulted lantern tower. The hall is decorated with arms and armour, including the suit of armour worn by King Henry VIII, made in 1540. The top of the stairs are flanked by life-size equestrian statues mounted by knights in armour. This theme of decoration continues into the Queen's Guard Chamber and the Grand Vestibule. Salvin also added the château-style conical roof to the Curfew Tower ("T") at this time.
John Sparrow David Thompson, 4th Prime Minister of Canada, died in the castle suddenly of a heart attack in 1894, while in office.
Following the accession of King Edward VII in 1901, the castle often remained empty for long periods, the new King preferring his other homes. The King visited for Ascot week and Easter. One of the few alterations he made was to lay out the castle's golf course.
Edward VII's successor George V, who was King from 1910 until his death in 1936, also preferred his other country homes. However, his wife Queen Mary was a connoisseur of the arts. She sought out and re-acquired long-dispersed items of furniture from the castle, but also acquired new works of art to furnish the state rooms. She also changed the way the castle was used, abandoning the idea of a large suite of state rooms reserved for important guests on the principal floor. New, more comfortable bedrooms with modern bathrooms were installed on the upper floors, allowing the formerly reserved state rooms below to be used for entertaining and court functions. The state bedroom itself was retained, but more as a historical curiosity. It has not been used as a bedroom since 1909.
During the First World War, when the members of the Royal Family felt the need to change its dynastic name from the German "House of Saxe-Coburg Gotha", they took their new name from the castle, becoming the "House of Windsor".
George VI came to the throne in 1936 following the abdication of his brother Edward VIII; on 11 December Edward had broadcast his abdication speech to the British Empire from Windsor castle, but had preferred during his short reign to live at Fort Belvedere in Windsor Great Park.
George VI (and his wife Queen Elizabeth) preferred their original Windsor home, Royal Lodge. On the outbreak of World War II in 1939 the castle resumed its role as a royal fortress, and the King and Queen and their children Princess Elizabeth (the future Queen Elizabeth II) and Princess Margaret lived, for safety, in the castle. The King and Queen drove daily to London, returning to Windsor to sleep, although for propaganda and morale purposes it was reported that the king was still residing full-time at Buckingham Palace. Following the cessation of hostilities in 1945, the Royal Family left Windsor Castle and returned to Royal Lodge.
In February 1952, Queen Elizabeth II came to the throne and decided to make Windsor her principal weekend retreat.
During the latter half of the 20th century Windsor Castle became one of Britain's major tourist attractions
On 20 November 1992, a fire which began in the Queen's private chapel quickly spread. The fire raged for 15 hours. It destroyed nine of the principal state rooms, and severely damaged over 100 more, in all the larger part of the upper ward. One-fifth of the floor space of the castle was damaged. The restoration programme was not complete until 1997. Although some of the rooms that had been gutted by the fire were completely redesigned in a modern interpretation, the new design is very organic and of the Gothic style, called "Downesian Gothic" after the rooms’ architect Giles Downes, of Sidell Gibson Partnership. These rooms include the new Private Chapel, the new Lantern Lobby and the new ceiling of St George's Hall. The last is made of green-oak, a technique used in medieval times.
During the Queen's tenure of the Castle much has been done, not only to restore and maintain the fabric of the building, but also to transform it into a major British tourist attraction. This has had to be achieved in co-ordination with the castle's role as a working royal palace.
To this day, the Waterloo Ceremony is still carried out in the presence of Her Majesty The Queen at Windsor each year.