The name 'Tartar' was already being applied to the Mongols in Western writings, even prior to their advance into Europe and the assimilation of their common designation 'Tatar' to Tartarus, the Hell of Classical Antiquity: the first Western author to use it was Quilichinus of Spoleto (1236). The Mongols' sudden retreat from Hungary, which certainly baffled contemporaries, has consequently been more difficult to explain than their first appearance. As Professor Sinor has pointed out, however, the qaghan's death would suffice to explain only the Mongol withdrawal had Batu proceeded to travel all the way to the Mongolian homeland to participate in the election of a successor. The claims of Carpini that the Mongols would have beaten a retreat had the Hungarians resisted manfully and of the author of the 'Tartar Relation' that they were on the point of flight when the Poles turned tail at Liegnitz.