Statue of the Duke of Devonshire, Whitehall

The execution of Charles I by beheading occurred on Tuesday 30 January 1649 outside the Banqueting House on Whitehall. The execution was the culmination of political and military conflicts between the royalists and the parliamentarians in England during the English Civil War, leading to the capture and trial of Charles I. On Saturday 27 January 1649, the parliamentarian High Court of Justice had declared Charles guilty of attempting to "uphold in himself an unlimited and tyrannical power to rule according to his will, and to overthrow the rights and liberties of the people" and he was sentenced to death.Charles spent his last few days in St James's Palace, accompanied by his most loyal subjects and visited by his family. On 30 January, he was taken to a large black scaffold constructed in front of the Banqueting House, where he was to be executed. A large crowd had gathered to witness the regicide. Charles stepped onto the scaffold and gave his last speech, declaring his innocence of the crimes of which parliament had accused him, and claiming himself as a "martyr of the people". The crowd could not hear the speech, owing to the many parliamentarian guards blocking the scaffold, but Charles' companion, Bishop William Juxon, recorded it in shorthand. Charles gave a few last words to Juxon, claiming his "incorruptible crown" in Heaven, and put his head on the block. He waited a few moments and gave a signal; the anonymous executioner beheaded Charles in one clean blow and held Charles' head up to the crowd silently, dropping it into the swarm of soldiers soon after. The execution has been described as one of the most significant and controversial events in English history. Some view it as the martyrdom of an innocent man, with Restoration historian Edward Hyde describing "a year of reproach and infamy above all years which had passed before it; a year of the highest dissimulation and hypocrisy, of the deepest villainy and most bloody treasons that any nation was ever cursed with" and the Tory Isaac D'Israeli writing of Charles as "having received the axe with the same collectedness of thought and died with the majesty with which he had lived", dying a "civil and political" martyr to Britain. Still others view it as a vital step towards democracy in Britain, with the prosecutor of Charles I, John Cook, declaring that it "pronounced sentence not only against one tyrant but against tyranny itself" and Whig historian Samuel Rawson Gardiner, who wrote that "with Charles' death the main obstacle to the establishment of a constitutional system had been removed. [...] The monarchy, as Charles understood it, had disappeared forever".

The Earl Haig Memorial is a bronze equestrian statue of the British Western Front commander Douglas Haig, 1st Earl Haig on Whitehall in Westminster, London. It was created by the sculptor Alfred Frank Hardiman and commissioned by Parliament in 1928. Eight years in the making, it aroused considerable controversy; the Field Marshal's riding position, his uniform, the horse's anatomy and its stance all drew harsh criticism. The inscription on the plinth reads 'Field Marshal Earl Haig Commander-in-Chief of the British Armies in France 1915–1918'.

The Royal United Services Institute (RUSI, Rusi), registered as Royal United Service Institute for Defence and Security Studies and formerly the Royal United Services Institute for Defence Studies, is a British defence and security think tank. It was founded in 1831 by the Duke of Wellington, Sir Arthur Wellesley.The current President of RUSI is the Duke of Kent and its Director-General is Karin von Hippel.

The equestrian statue of Prince George, Duke of Cambridge is a life-size memorial by Adrian Jones, installed in Whitehall, London.

The Holbein Gate was a monumental gateway across Whitehall in Westminster, constructed in 1531–32 in the English Gothic style. The Holbein Gate and a second less ornate gate, Westminster Gate, were constructed by Henry VIII to connect parts of the Tudor Palace of Whitehall to the east and west of the road. It was one of two substantial parts of the Palace of Whitehall to survive a catastrophic fire in January 1698, the other being Inigo Jones's classical Banqueting House. The Holbein Gate was described by Thomas Pennant as "the most beautiful gate at Whitehall". It was demolished in 1759.The name of Holbein Gate reflects a tradition that it was designed by Hans Holbein, although any connection with Holbein seems unlikely. It was also known as the King's Gate or the Cockpit Gate, being close to the Royal Cockpit. The Westminster Gate or Kings Street Gate further south was built in a simpler more classical style with circular corner towers and domed turrets, and was demolished in 1723. The Holbein Gate is shown in drawings and engravings, including an engraving made by George Vertue in 1725 and published in 1747 in Vol. I of Vetusta Monumenta. The gate was a rectangular building of three floors, with the principal rooms on the upper two floors. Projecting square bases on each corner supporting octagonal towers and turrets. A passageway between the towers approximately 12 feet (3.7 m) wide allowed traffic to pass beneath a flat archway, with one footway to the east and possibly a second footway to the west through the towers (although the west footway may have been blocked and then cleared). Above the arch was an oriel window with two row of six lights (one to either side and four in the centre) on the first floor, and a window of four lights in a double row on the first floor. The top of the tower was surmounted by a parapet with battlements. Each face of the octagonal towers had two-light windows in double rows. Both sides of the gate were faced with chequerboard patterns of flint and stone, and also decorative carved panels, including a royal coat of arms above the arch, gryphons holding shields, and other royal emblems, such as the portcullis, fleur-de-lys and Tudor rose. Roundels to either side of the large central windows held with busts, possibly by Giovanni da Maiano. (Three terracotta busts by Pietro Torrigiano owned by the Wright family in Hatfield Peverel until the 1920s were thought to come from the Gate, but later scholarship doubts any connection.) The arch was later filled in down to the springing, flattening its profile. A gallery to the west overlooked the Royal Tiltyard (now Horse Guards Parade) leading eventually to St James's Park. Another gallery led to the Cockpit. The upper storey was used as the Paper Office, from perhaps 1672 until 1756. The lower storey was used as lodgings. Residents included Duke of Lennox in around 1620, later General Lambert until 1657 and then Viscount Fauconberg. It was occupied by Lady Castlemaine from around 1664 to around 1670 and then by her daughter, the Countess of Sussex. William Van Huls, Clerk of the Queen's Robes and Wardrobes, was the occupant in 1712. Like the gate at Temple Bar on Fleet Street, the Holbein Gate obstructed the movement of traffic along the road below. Proposals for its demolition were put forward in the early part of the 18th century, but were successfully opposed by John Vanbrugh and others. The gate was left in place when the King Street Gate was demolished in 1723, but the filled-in segment of the arch was cleared to increase headroom for traffic passing below. The adjacent red brick Van Huls house (depicted by Canaletto in a painting of 1747 at Goodwood House) was acquired in March 1759, and the arch and the house were demolished in August 1759. There were plans for the Duke of Cumberland to rebuild the gate in Windsor Great Park, but in the end it seems that the materials were incorporated in repairs to other buildings.

Whitehall is a road and area in the City of Westminster, Central London. The road forms the first part of the A3212 road from Trafalgar Square to Chelsea. It is the main thoroughfare running south from Trafalgar Square towards Parliament Square. The street is recognised as the centre of the Government of the United Kingdom and is lined with numerous departments and ministries, including the Ministry of Defence, Horse Guards and the Cabinet Office. Consequently, the name 'Whitehall' is used as a metonym for the British civil service and government, and as the geographic name for the surrounding area. The name was taken from the Palace of Whitehall that was the residence of Kings Henry VIII through to William III, before its destruction by fire in 1698; only the Banqueting House has survived. Whitehall was originally a wide road that led to the front of the palace; the route to the south was widened in the 18th century following the destruction of the palace. As well as government buildings, the street is known for its memorial statues and monuments, including the UK's primary war memorial, the Cenotaph. South of the Cenotaph the thoroughfare becomes Parliament Street. The Whitehall Theatre (now the Trafalgar Studios) was formerly associated with a series of farces.

The Banqueting House, Whitehall, is the grandest and best known survivor of the architectural genre of banqueting house, which were constructed for elaborate entertaining. It is the only remaining component of the Palace of Whitehall, the residence of English monarchs from 1530 to 1698. The building is important in the history of English architecture as the first structure to be completed in the neo-classical style, which was to transform English architecture.Begun in 1619 and designed by Inigo Jones in a style influenced by Andrea Palladio, the Banqueting House was completed in 1622 at a cost of £15,618, 27 years before King Charles I of England was beheaded on a scaffold in front of it in January 1649. The building was controversially re-faced in Portland stone in the 19th century, though the details of the original façade were faithfully preserved. Today, the Banqueting House is a national monument, open to the public and preserved as a Grade I listed building. It is cared for by an independent charity, Historic Royal Palaces, which receives no funding from the British Government or the Crown.

Gwydyr House (Welsh: Tŷ Gwydyr) is a Grade II* listed mansion in Whitehall, and is the London headquarters of the Office of the Secretary of State for Wales. The house lies on the eastern side of the street, opposite Dover House.

The Palace of Whitehall – also spelled White Hall – at Westminster was the main residence of the English monarchs from 1530 until 1698, when most of its structures, with the notable exception of Inigo Jones's Banqueting House of 1622, were destroyed by fire. Henry VIII moved the royal residence to White Hall after the old royal apartments at the nearby Palace of Westminster were themselves destroyed by fire. Although the Whitehall palace has not survived, the area where it was located is still called Whitehall and has remained a centre of the British government. White Hall was at one time the largest palace in Europe, with more than 1,500 rooms, overtaking the Vatican, before itself being overtaken by the expanding Palace of Versailles, which was to reach 2,400 rooms. At its most expansive, the palace extended over much of the area bordered by Northumberland Avenue in the north; to Downing Street and nearly to Derby Gate in the south; and from roughly the elevations of the current buildings facing Horse Guards Road in the west, to the then banks of the River Thames in the east (the construction of Victoria Embankment has since reclaimed more land from the Thames)—a total of about 23 acres (9.3 ha). It was about 710 yards (650 m) from Westminster Abbey.

The War Office was a department of the British Government responsible for the administration of the British Army between 1857 and 1964, when its functions were transferred to the new Ministry of Defence (MoD). It was equivalent to the Admiralty, responsible for the Royal Navy (RN), and (much later) the Air Ministry, which oversaw the Royal Air Force (RAF). The name 'War Office' is also given to the former home of the department, located at the junction of Horse Guards Avenue and Whitehall in central London. The landmark building was sold on 1 March 2016 by HM Government for more than £350 million, on a 250 year lease for conversion into a luxury hotel and residential apartments. Prior to 1855, 'War Office' signified the office of the Secretary at War. In the 17th and 18th centuries, a number of independent offices and individuals were responsible for various aspects of Army administration. The most important were the Commander-in-Chief of the Forces, the Secretary at War, and the twin Secretaries of State; most of whose military responsibilities were passed to a new Secretary of State for War in 1794. Others who performed specialist functions were the controller of army accounts, the Army Medical Board, the Commissariat Department, the Board of General Officers, the Judge Advocate General of the Armed Forces, the Commissary General of Muster, the Paymaster General of the forces, and (particularly with regard to the Militia) the Home Office.The term War Department was initially used for the separate office of the Secretary of State for War; in 1855, the offices of Secretary at War and Secretary of State for War were amalgamated, and thereafter the terms War Office and War Department were used somewhat interchangeably.

The Cockpit-in-Court (also known as the Royal Cockpit) was an early theatre in London, located at the Palace of Whitehall, next to St. James's Park, now the site of 70 Whitehall, in Westminster. The structure was originally built by Henry VIII, after he had acquired Cardinal Wolsey's York Place to the north of the Palace of Westminster, following the Cardinal's downfall in 1529. It was one of a number of new pleasure buildings constructed for King Henry's entertainment, including a real tennis court, a bowling alley, and a tiltyard, and was used as an actual cockpit; that is, an area for staging cockfighting. Thus enlarged, the Palace of Whitehall became the main London residence of the Tudor and Stuart Kings of England, and the Palace of Westminster was relegated to ceremonial and administrative purposes only. The Cockpit ceased to be used for cockfighting in Jacobean times, and was used instead as a private theatre and as chambers for members of the Royal Household. It was redesigned in 1629 for Charles I by Inigo Jones as a private venue for staging court masques. It was the second cockpit that Jones had redesigned as a theatre, the other being the Cockpit Theatre in Drury Lane, which was renovated after a fire in 1617. After the London theatre closure of the Interregnum, the Cockpit returned to use under Charles II, and was refitted in 1662. A new dressing room was added for female players, whose presence onstage was a recent theatrical innovation; its walls were decorated with green baize, one possible origin of the theatrical term "green room" for a dressing room. Samuel Pepys records attending several plays at the Cockpit in his diary. In 1680, it was occupied by the Duke of Albemarle in his official capacity as Master of the Great Wardrobe, and later by Ralph, 1st Duke of Montagu in the same capacity. Charles II gave the Cockpit to Princess Anne, daughter of Charles's brother James, Duke of York, in 1683. Anne and her closest friend, Sarah, Lady Churchill were imprisoned here during the Glorious Revolution; both their husbands, Prince George of Denmark and John, Baron Churchill switched their allegiances from James II to William of Orange. Sarah and Anne escaped to Nottingham shortly afterwards. The Palace of Whitehall was almost completely destroyed by fire in 1698. One prominent structure to survive was the Banqueting House, also designed by Inigo in 1619; another, lesser, structure to survive, was the Cockpit. After the fire, William III moved his London residence to nearby St James's Palace, and the site was rebuilt to be used as government offices, and residential and commercial premises. The Cockpit was used to house government officials. It was first occupied by HM Treasury, whose offices elsewhere in the palace had been destroyed, until the Treasury moved to a new building on Horse Guards Road in 1734.When Anne became queen after the death of William in 1702, she gave the residence to her loyal friends John and Sarah, now Duke and Duchess of Marlborough. They vacated the residence during Anne's reign and it became the Treasury. After the Treasury moved, it was used in the late 18th century by the Foreign Office, after that government office had been founded at Cleveland Row, St James's but before it moved to Downing Street. Next, it was used by the Privy Council as a council chamber, for judicial purposes. It continued to be used by the Privy Council after a new chamber was built for them in 1827. The current building on the site, at 70 Whitehall, is used by the Cabinet Office. The reconstructed Cockpit Passage in 70 Whitehall runs along the edge of the old tennis courts and into Kent's Treasury, built on the site of the original cockpit lodgings. The minstrel's gallery on the ground floor is currently decorated with pictures of fighting cocks and a model of the old Whitehall palace. It should not be confused with Cockpit Steps nearby in St James Park, which lead up from Birdcage Walk past the site of a royal cockpit in Old Queen Street.

Dover House is a Grade I-listed mansion in Whitehall, and the London headquarters of the Scotland Office. The building also houses the Office of the Advocate General for Scotland and the Independent Commission for Aid Impact.