OK, it’s a blackjack. We know it was used for drinking beer, but why was it called a “blackjack”? The “black” is obvious — it’s the color of the leather after it has been treated with pitch or wax to make it waterproof.
A “jack” was a straight-sided leather jerkin that flared out at the hips that medieval English archers wore in battle. French archers called it un jaque d’Anglois. Put the two together, and voila, “blackjack”!
Blackjacks are almost exclusively English and were looked down upon by the more sophisticated (in their eyes) French. In 1614, when Henri III of France asked Monsieur Daudelot what especial things he had noted in England during his negotiations there, he answered that he had seen “but three things remarkable”: which were “that people did drinke in bootes, eat raw fish, and strewed all their best rooms with hay” — referring to blackjacks, oysters, and rushes.
And in his drama Edward IV, first published in 1599, Thomas Heyward wrote of blackjacks at the Court, “which when the French-men first saw, they reported on their return to their countrey that the Englishmen used to drink out of their Bootes.”
From the Guildhall records of the leathercrafters, we know that leather vessels were made in large quantities in the 1300s. In 1350, the Ordinances of the Bottilars of London empowered them to make botellis et aliis vasis de corro (bottles and other vessels of leather).
Leather had many advantages. Very few pottery tankards were made in medieval England, though some, especially stoneware ones, were imported from the continent and were therefore expensive. But pottery broke easily, as did glass. Treen tankards, or “cans,” were at least breakproof, but leather was even better: In 1397, the buttery of the Priory of Finchale contained four small jacks and eight large cans of wood, but wooden cans do not last, and when the next inventory was taken in 1411, the wooden cans had been replaced by six large drinking jacks.
Today, genuine blackjacks are comparatively rare, and their consequent high prices have encouraged them to be reproduced — with honest and dishonest intent. In fakes and repros the bottom is often flush with the sides, not deeply recessed, and the handles are often stitched on, sometimes using metal thread: in a genuine blackjack the handles are generally the same piece of leather as the body of the vessel and continuous with it, and the bottoms are recessed to preserve them from wear. Both of these features require high skill from the leatherworker, a skill the faker did not possess.