For British schoolchildren, 1066 is a talismanic year: the year of the Norman Conquest, when a dispute over the royal succession transformed the entire structure of England.

William, the duke of Normandy — that’s whom Harold has gone abroad to meet — will cross the Channel himself in 1066, and rout Harold’s forces at the Battle of Hastings on Oct. 14. By Christmas, the foreigner will be crowned at Westminster Abbey, as William I of England. To posterity, he will be known as William the Conqueror. The conquest is reliably illustrated in those students’ textbooks with images of the Bayeux Tapestry, a 230-foot textile record of William’s victory.

It was stitched in the 1070s, historians believe, probably by secular English women working in Canterbury or nearby. Thereafter — no one knows when; uncertainty is going to be a theme here — it went to Bayeux, in northern France. It has taken nearly 1,000 years to bring it back to Britain, where until next July the tapestry is at the British Museum in an exhibition of unparalleled diplomatic significance.

King Charles III, who still signs the British Parliament’s bills into law in the Norman French of his predecessor, was on hand last week to inaugurate the exhibition. So was President Emmanuel Macron of France, who masterminded the loan as part of a post-Brexit détente.

To judge from the advance sales and the media saturation, Macron hit the mark. The first tranche of tickets (costing nearly $45) sold out in less than a day. The challenge of getting in now currently approaches Birkin bag-level difficulty.