This mysterious object seems to relate to ivory chessmen of the Middle Ages. The Walters Art Gallery, Baltimore possesses a Scandinavian rook with a comparable pose and very simiilar facial features (inv. no. 71.1157). The ring-and-dot decorations are often employed in gaming pieces -see for example three English circular gaming pieces in the Victoria and Albert Museum (inv. nos. A.20 to A.22-1942)- but are also commonplace in early art from outside Europe.
R. H. Randall, Jr. (ed.), Masterpieces of ivory from the Walters Art Gallery, London, 1985, pp. 176-77, no. 529; P. Williamson, Medieval ivory carvings. Early Christian to Romanesque, cat. Victoria and Albert Museum, London, 2010, p. 416, no. 105