Lewis chessmen owned by British Museum
The Lewis chessmen (Norwegian: Lewisbrikkene; Scottish Gaelic: Fir-Tàilisg; Scots: Lewis chesmen) or Uig chessmen, named after the island or the bay where they were found, are a group of distinctive 12th-century chess pieces, along with other game pieces, most of which are carved from walrus ivory. Discovered in 1831 on Lewis in the Outer Hebrides of Scotland, they may constitute some of the few complete, surviving medieval chess sets, although it is not clear if a period-accurate set can be assembled from the pieces. When found, the hoard contained 93 artifacts: 78 chess pieces, 14 tablemen and one belt buckle. Today, 82 pieces are owned and usually exhibited by the British Museum in London, and the remaining 11 are at the National Museum of Scotland in Edinburgh.
Additionally, a newly identified piece, a "warder", the equivalent of a castle or rook, was sold for £735,000 in July 2019.  Four other major pieces, and many pawns,  remain missing from the chess sets.Origin
Most accounts have said the pieces were found at Uig Bay (58°11′10″N 7°01′19″W) on the west coast of Lewis, but Caldwell et al. of National Museums Scotland (NMS) consider that Mealista (58°06′14″N 7°06′29″W)—which is also in the parish of Uig and some 6 miles (10 km) further south down the coast—is a more likely place for the hoard to have been discovered. The hoard was divided and sold in the 19th century; the British Museum (BM) holds 82 pieces, and National Museums Scotland has the other 11 pieces.At the British Museum, Sir Frederic Madden, Assistant Keeper of Manuscripts, persuaded the trustees to purchase for 80 guineas (£84) the 82 pieces which he had been misled into believing was the entire hoard. Madden was a palaeographer, a scholar of early vernacular literature, but he was especially intrigued by these artifacts because he was a chess enthusiast. Madden immediately set about writing a monumental research paper about the collection, titled "Historical remarks on the introduction of the game of chess into Europe and on the ancient chessmen discovered in the Isle of Lewis", published in Archaeologia XXIV (1832), one that remains informative and impressive today.There are many medieval chess bishops of various origins in different museums in Europe and US. A bishop that probably predates the Lewis chessmen was in the collection of Jean-Joseph Marquet de Vasselot and was sold at Christie's in Paris in 2011 with a radiocarbon dating report stating that there is a 95% probability that the ivory dates between 790 and 990 AD. It is thought to be English or German and carved in the 12th century. Stylistically it predates the Lewis chessmen, as its mitre is worn sideways.
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