The Most Ancient and Most Noble Order of the Thistle is an order of chivalry, associated with Scotland. Its original date of founding is unknown. James VII (also King of England as James II) created the modern Order in 1687. The Order is the Sovereign and sixteen Knights and Ladies, as well as certain "extra" knights (members of the British and foreign royal families). The Sovereign decides who is to be a member. He or she is not advised by the Government, as occurs with most other Orders. The sixteen members are required to be Scottish-born, but  the "extra" knights and ladies are not.

The Order's main emblems are the thistle, the national flower of Scotland, and Saint Andrew holding a saltire (X shaped cross).  The motto is Nemo me impune lacessit (Latin for "No one provokes me with impunity"); the same motto is also on the Royal Coat of Arms of the United Kingdom for use in Scotland and on some pound coins. St Andrew is also the patron saint of the Order.

Most British orders of chivalry cover all of the United Kingdom, but the three most most senior ones each cover only one constituent country . The Order of the Thistle, which covers to Scotland, is the second-most senior in precedence. Its equivalent in England, The Most Noble Order of the Garter, is the oldest order of chivalry in the United Kingdom, dating to the middle fourteenth century. In 1783 an Irish order, The Most Illustrious Order of St Patrick, was founded; but since the independence of the Republic of Ireland the Order has fallen dormant. The last new knight was made in 1927, and the last surviving Knight of St Patrick died in 1974.

History

The first date of the Order's creation is not known. One story says that Achaius, King of Scots,  was fighting King Aethelstan of East Anglia and he saw cross of St Andrew in the sky.  After he won the battle, Achaius established the Order of the Thistle. Even though Achaius and Aethelstan never fought, this story of the foundation, is given in the Royal Warrant 'reviving' the Order in 1687.  Another story says that the Order was instituted, or re-instituted by Robert I at the Battle of Bannockburn.

King James II and VII issued letters patent "reviving and restoring the Order of the Thistle to its full glory, lustre and magnificency" in 1687.  Only 12 knights were allowed, and he appointed eight before the King was deposed in 1688.  His successors, the  William and Mary, did not make any more appointments to the Order. In 1703 however, Anne once again revived the Order of the Thistle.

Composition

The Kings of Scotland–later the Kings of Great Britain and of the United Kingdom–have served as Sovereigns of the Order.

When James VII revived the Order, the statutes said that the Order would continue the ancient number of Knights, which was described in the preceding warrant as "the Sovereign and twelve Knights-Brethren in allusion to the Blessed Saviour and his Twelve Apostles.

In 1827, George IV increased the Order to sixteen members. Women were excluded from the Order.  George VI created his wife Elizabeth Bowes-Lyon a Lady of the Thistle in 1937, and in 1987 Elizabeth II allowed the regular admission of women to both the Order of the Thistle and the Order of the Garter.

From time to time, individuals joined the Order by special permission. These members are known as "Extra Knights" and do not count towards the sixteen-member limit. Members of the British Royal Family are normally admitted by special permission; the first was Prince Albert.  King Olav V of Norway, was the first foreigner to be admitted to the Order, was also admitted by special permission in 1962.

The Sovereign has historically had the power to choose Knights of the Order. From the eighteenth century onwards, the Sovereign made his or her choices upon the advice of the Government. George VI felt that the Orders of the Garter and the Thistle had been used only for political patronage, rather than to reward actual merit. Therefore in 1946, with the agreement of the Prime Minister (Clement Attlee) and the Leader of the Opposition (Winston Churchill), both Orders returned to the personal gift of the Sovereign.

Knights and Ladies of the Thistle may also be admitted to the Order of the Garter. 

Knights and Ladies of the Thistle may also have their knighthoods taken away. But this has happened only once, to John Erskine, 6th Earl of Mar who was deprived of  both the knighthood and the earldom after taking part in the Jacobite rising of 1715.

The Order has five officers: 
 the Dean - a minister of the Church of Scotland
 the Chancellor - who keeps the seal of the order
 the Usher of the Green Rod
 the Secretary
 the King of Arms

Uniform

For the Order's great occasions, such as its annual service each June or July, as well for coronations, the Knights and Ladies wear an elaborate costume:

The mantle is a green robe worn over their suits or military uniforms. The mantle is lined with white taffeta; it is tied with green and gold tassels. On the left shoulder of the mantle is the star of the Order
The hat is made of black velvet and has white feathers with black egret or heron's feathers in the middle.
The collar is made of gold and depicts thistles and sprigs of rue. It is worn over the mantle.
The St Andrew, also called the badge-appendant, is worn hanging from the collar. It comprises a gold enamelled picture of St Andrew, wearing a green gown and purple coat, holding a white saltire.

Aside from these special occasions, however, much simpler badges are used whenever a member of the Order attends an event at which decorations are worn.

The star of the Order is a silver St Andrew's saltire, with clusters of rays between the arms. In the centre is depicted a green circle bearing the motto of the Order in gold letters; in the circle is a thistle on a gold field.
The broad ribbon is a dark green sash worn across the body, from the left shoulder to the right hip.
At the right hip of the sash, the badge of the Order is attached. The badge depicts St Andrew in the same form as the star surrounded by the Order's motto.

Chapel

When James VII revived the Order in 1687, he wanted the Abbey Church at the Palace of Holyroodhouse to be the Chapel for the Order of the Thistle, perhaps copying the idea from the Order of the Garter (whose chapel is located in Windsor Castle). 

James VII was deposed by 1688 and the Order did not have a Chapel until 1911, when one was added onto St Giles High Kirk in Edinburgh. Each year, the Sovereign stays at the Palace of Holyroodhouse in June or July; during the visit, a service for the Order is held. Any new Knights or Ladies are installed at annual services. 

Each member of the Order, including the Sovereign, is allotted a seat in the Chapel.  Their coat of arms is above their seat.

Current members and officers 
 Sovereign: Elizabeth II
 Knights and Ladies Companion:
  The Earl of Elgin and Kincardine  (1981)
  The Earl of Airlie  (1985)
  The Earl of Crawford and Balcarres  (1996)
  The Lord Macfarlane of Bearsden  (1996)
  The Lord Mackay of Clashfern  (1997)
  The Lord Wilson of Tillyorn  (2000)
  Sir Eric Anderson  (2002)
  The Lord Steel of Aikwood  (2004)
  The Lord Robertson of Port Ellen  (2004)
  The Lord Cullen of Whitekirk  (2007)
  The Lord Hope of Craighead  (2009)
  The Lord Patel  (2009)
  The Earl of Home  (2014)
  The Lord Smith of Kelvin  (2014)
  The Duke of Buccleuch and Queensberry  (2017)
  Sir Ian Wood  (2018)
 Extra Knights and Ladies Companion:
  Prince Philip, Duke of Edinburgh  (1952)
  Prince Charles, Duke of Rothesay  (1977)
  Anne, Princess Royal  (2000)
  Prince William, Earl of Strathearn  (2012)
 Officers:
 Chancellor: The Earl of Airlie  
 Dean: The Reverend Professor David Fergusson, 
 Secretary:  Elizabeth Roads  
 Lyon King of Arms: Joseph Morrow,  (Lord Lyon King of Arms)
 Gentleman Usher of the Green Rod: Rear Admiral Christopher Hope Layman

References 

 
British monarchy
1687 establishments
17th-century establishments in Scotland
1680s establishments in Europe