St. George's Chapel in Windsor Castle has been the home of the Most Noble Order of the Garter since King Edward III of England founded the Order in 1348 as "a society, fellowship and college of knights." It is now the oldest and highest order of chivalry in the British honours system.

In conscious imitation of King Arthur's Round Table, the Order always has twenty-five official Knights of the Garter, plus the Sovereign, and each is assigned a seat in the choir of the Chapel; each knight's coat of arms is displayed on a flag hanging over that seat. Women are now admitted to the Order, as are a few non-Christian foreign heads of state. Since 1786 there have also been extra ("supernumerary") knights, not counted in the twenty-five, to include certain ex officio personages, such as all the sons of the sovereign.

As with the other orders of chivalry, the sovereign fills vacancies in the membership by naming persons who have performed some noteworthy service for the nation. Knights may use the post nominal "K.G." after their names, while Ladies use "L.G."

The Order has various insignia:

• The Garter is dark blue velvet buckled strap bearing the motto Honi soit qui mal y pense (Shame on him who thinks evil of it) in gold letters. It is worn by a Knights below the left knee and by Ladies on the upper left arm.
• The Collar is a gold chain, consisting of twenty-four pieces, each piece consisting of an enamelled Tudor rose surrounded by a representation of the Garter, connected by twenty-four knots of gold. It is worn around the neck.
• The George is an enamelled figure of St George slaying a dragon. It is worn suspended from the collar.
• The Lesser George is a gold badge showing St George slaying a dragon. It is worn on a ribbon placed over the left shoulder.
• The Star is a silver eight-pointed figure, with the Cross of St George, encircled by a representation of the Garter, in the centre.
• The Mantle is a dark blue velvet coat, with a white shield, surrounded by a representation of the Garter, bearing the Cross of St George, on the left shoulder.
• The Hood and Surcoat are of crimson velvet.
• The Hat is of black velvet and is plumed with white ostrich feathers.

The Order of the Garter has five officers, three of whom are clergymen of the Church of England. The office of Prelate of the Order is always held by the Bishop of Winchester, that of Chancellor by the Bishop of Oxford, and that of Register by the Dean of Windsor. The two lay officers are the Officer of Arms, the Garter Principal King of Arms, and the Usher, the Gentleman Usher of the Black Rod.

The 25 Knights Founders of the Garter (1348)

1. Edward, the Black Prince, Prince of Wales (1330-1376)
2. Henry of Grosmont, Duke of Lancaster, Admiral of the Fleet and Steward of England (1300-1360/1)
3. Thomas Beauchamp, 3rd Earl of Warwick, Marshal of England (1314-1369)
4. Jean de Grailly, Captal de Buch (d.1377)
5. Ralph Stafford, 1st Earl of Stafford (1301-1372)
6. William de Montacute, 2nd Earl of Salisbury (1328-1397)
7. Roger Mortimer, 2nd Earl of March (1328-1359/60)
8. Sir John de Lisle, later 1st Lord Lisle de Rougemont (d.1356)
9. Sir Bartholmew Burghersh (d.1369)
10. Sir John Beauchamp, later 1st Lord Beauchamp de Warwick (d.1360)
11. John Mohun, 2nd Lord Mohun (d.1376)
12. Sir Hugh Courtenay (d. before Sept. 2, 1349)
13. Sir Thomas Holland, afterwards 1st Earl of Kent (d.1360)
14. Sir John Grey (d.1359)
15. Sir Richard Fitz-Simon (latest notice 1347/8)
16. Sir Miles Stapleton (d.1364)
17. Sir Thomas Wale (d.1352)
18. Sir Hugh Wrottesley (d.1380/1)
19. Sir Male Loryng (d.1385/6)
20. Sir John Chandos (d.1369)
21. Sir James Audley (d.1369)
22. Sir Otho Holand (d.1359)
23. Sir Henry Eam (d.before 1360)
24. Sir Sanchet d'Abrichecourt (latest notice Oct. 20, 1345)
25. Sir Walter Paveley (d.1375)

Later Knights of the Garter

• Knights of the Garter (1349-1699)
• Knights of the Garter (1700-1899)
• Knights of the Garter (after 1899)
• Ladies of the Garter (1358-1488)