Speculation was rife among the crowd that Kate Middleton had come to St George’s Chapel, Windsor, yesterday to check out a wedding venue.

But such fancy was premature. She was there to witness the spectacle of her boyfriend, Prince William, being installed as a Knight of the Garter, the world’s oldest surviving order of chivalry and the absolute top echelon in Britain’s arcane system of honours.

William looked fetching, if mildly embarrassed, as he walked in procession with other members of the royal family and a phalanx of Knights Companion, all dressed in blue velvet mantle, garter on left leg and over-the-top hat of ostrich and heron feathers. At least it made a change from all those pictures of William in assorted military uniforms we have seen recently.

Ms Middleton, as an invited guest, was dressed in plain black, with a vast black straw hat tipped forward to cover her face. She watched the procession from the Galilee Porch on the side of the chapel with Prince Harry. They both laughed and giggled as William walked past with his father, the Prince of Wales, as though sniggering at their elaborate fancy dress.

The crowd of 7,000 at the castle baked in the June sunshine as the Household Cavalry band played the knights in to Walton’s Crown Imperial. (Ms Middleton was probably too far away to hear them play, as she stepped from her Ford Mondeo, the theme from Pirates of the Caribbean.)

William’s appointment as by far the youngest Garter Knight was announced, as is the custom, on St George’s Day. Yesterday was his formal installation; at a private ceremony in the Garter Throne Room in the castle, his grandmother buckled on his Garter just below his left knee.

After the ceremony the Garter Knights were treated to lunch by the Queen, for which they remove their cloaks, to avoid gravy stains. Apart from the costume and the kudos, a good lunch once a year is more or less the only benefit of being a KG.

During the following hour-long service, William was conducted to his stall by Garter King of Arms and Black Rod, where his shield and banner will be installed. Two other new KGs, Lord Luce, the former Lord Chamberlain, and Sir Thomas Dunne, Lord-Lieutenant of Herefordshire, were also installed, filling vacancies created by the deaths of Sir Edward Heath and Sir Edmund Hillary. Appointment to the Garter, which outranks all other knighthoods, is in the personal gift of the Queen. It supposedly rewards exceptional service to monarch and nation, so its current members include Bramall the field marshal, Sainsbury the grocer and Bingham the ex-Lord Chief Justice.

Edward III created the order in 1348. Tradition has it that while dancing with Joan, Countess of Salisbury, at a court ball, her garter fell to the floor and the King chivalrously picked it up, uttering the order’s motto, which appears on the front of British passports. If that were true, Honi Soit Qui Mal Y Pense could translate as “don’t even think about it, you dirty-minded little knights”.

More plausible is the idea that Edward shared medieval fascination with the Arthurian legend and created his own Round Table. In which case the motto translates more accurately as “evil to him who thinks evil”.

The Garter is usually offered to past prime ministers; Sir John Major walked in procession yesterday while Baroness Thatcher, increasingly frail, was delivered to the chapel door by car. History suggests that we should see Tony Blair in that June procession one day. And they will probably have to give it to Prince Harry too.

He will have to behave himself, as knights deemed to have “degraded” the order can be thrown out. Kaiser Wilhelm was stripped of his Garter, and Emperor Hirohito, although his son Akihito is a member. Mere high jinks in nightclubs would probably be forgiven.

Companions in arms

Sovereign of the Order The Queen

Ladies of the Order The Princess Royal (1994), Princess Alexandra (2003)

Royal Knights Duke of Edinburgh (1947), Prince of Wales (1958), Duke of Kent (1985), Duke of Gloucester (1997), Duke of York (2006), Earl of Wessex (2006), Prince William of Wales (2008)

Extra Knight Companions and Ladies (foreign royal members) Grand Duke Jean of Luxembourg (1972), Queen Margrethe II of Denmark (1979), King Carl XVI Gustaf of Sweden (1983), King Juan Carlos I of Spain (1988), Queen Beatrix of the Netherlands (1989), Emperor Akihito of Japan (1998), King Harald V of Norway (2001)

Knights and Lady Companions (a maximum of 24)

Duke of Grafton (1976), Lord Richardson of Duntisbourne (1983), Lord Carrington (1985), Duke of Wellington (1990), Lord Bramall (1990), Viscount Ridley (1992), Lord Sainsbury of Preston Candover (1992), Lord Ashburton (1994), Lord Kingsdown (1994), Sir Ninian Stephen (1994), Baroness Thatcher (1995), Sir Timothy Colman (1996), Duke of Abercorn (1999), Sir William Gladstone of Fasque and Balfour (1999), Lord Inge (2001), Sir Antony Acland (2001), Duke of Westminster (2003), Lord Butler of Brockwell (2003), Lord Morris of Aberavon (2003), Sir John Major (2005), Lord Bingham of Cornhill (2005), Lady Soames (2005), Lord Luce (2008), Sir Thomas Dunne (2008)

Source: Whitaker’s Almanack

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