Ivory Vikings: The Mystery of the Most Famous Chessmen in the World and the Woman Who Made Them. By Nancy Marie Brown. St. Martin’s Press; 288 pages; $26.99.

IN 2010 an amateur Icelandic historian gatecrashed an international symposium on the Lewis chessmen, the greatest cache of medieval game pieces ever found. Gudmundur Thorarinsson, a chess-player (and an engineer by profession), hoped to convince the assembled scholars that the 92 walrus ivory pieces unearthed on the Isle of Lewis, off the west coast of Scotland, in 1831 were the work of a woman carver commissioned by a medieval Icelandic bishop. He was dismissed as a “nuthead”. Though no one really knows where the chessmen were made, the consensus of curators of the Lewis hoard held by the British Museum and the National Museum of Scotland is that they probably originated in Norway late in the 12th century.

Mr Thorarinsson’s theory, however, caught the eye of Nancy Marie Brown, an American who has written extensively on the Viking age. Alerted by the disparaging of medieval Iceland as a “scrappy place full of farmers”, she begged to differ. The result is “Ivory Vikings”, the absorbing story of long-ago links between the British Isles and Scandinavia that puts the Lewis chessmen into a vivid and much broader cultural context of Viking trade, plunder and sophisticated gift-giving.

These stolid, expressive little figurines are star draws in the museums that possess them. Ms Brown aptly calls them “Norse netsuke” (after the little Japanese carvings), shaped with skill and whimsy from what the Icelandic sagas term “fish teeth”: the queens, one hand pressed in alarm or woe to a cheek; the grim kings with braided hair, thrones elaborately detailed with Romanesque loops; the doughty, somewhat ludicrous knights; mitred bishops; and most of all the rooks, several biting their shields, unmistakably representations of Viking “berserks”, the warriors of the Norse god Odin.

The pieces, which come from several sets, are the earliest to include bishops, and also among the first to include queens rather than counts and viziers, highlighting the evolution of the war game as it travelled from India to Europe. Ms Brown uses her extensive knowledge of Icelandic literature to try to deduce just who might have put those bishops and queens on the board. Her book is a social history that romps through the evolution of chess, walrus hunting in the far north, Viking marauding from the Mediterranean to the Caspian seas, and recent discoveries of walrus tusks and carvings across the North Atlantic that reveal the Vikings as “players in a huge cultural network, trafficking in goods and ideas”.

Ultimately she concurs with the amateur who argued that Bishop Pall Jonsson of Skalholt in Iceland might well have commissioned the Lewis chessmen from his favourite carver, one Margret the Adroit. The 13th-century “Saga of Bishop Pall” describes an aesthete fond of lavish gifts: beautifully carved crosiers of walrus ivory he sent to fellow bishops, made by Margret, “who at that time was the most skilled carver in all Iceland”. At a time of strife between king and pope over who wielded authority, Ms Brown argues, Bishop Pall Jonsson was the Norse bishop “whose role in real life most closely matches that of the bishop on the chessboard”.

Despite the book’s subtitle, readers learn frustratingly little about Margret; the historical record is too lean. But the story bristles with fascinating facts: walrus tusks were so valuable that they were “Arctic gold”; 80% of farm names on Lewis are Norse. The Scottish National Party insisted last year that if the independence referendum passed, the treasures should be repatriated. The mystery of their finding is as deep as that of their making, involving secrets that intersect with the Highland Clearances and Sir Walter Scott.

Ms Brown describes landscapes and her Norsemen and women with a lucid, dry humour. Though rather too heavy on the sagas, with their dizzying procession of chieftains and kings, she has done the reader a great service by widening the debate into an engaging, accessible tale.