Meantime, the Venetians were growing wealthy, and Marco’s father and uncle were growing old; and increasing wealth and increasing years raised in them an apprehension of what might befall them in case of the aged Khan’s death, and a desire to return to their native land. Several times they applied to Kublai for permission to depart; but he was loth to say farewell to the men whom he had known and trusted so long, and, but for an opportune event, they might never have succeeded in carrying themselves and their jewels and gold back to Europe. In 1286 Arghún Khan, of Persia, Kublai’s great-nephew, lost his favourite wife, the Khatun Bulaghán. On her death-bed she charged him to supply her place with a daughter of her own tribe, the Mongols of Bayaut; and, desirous of fulfilling her dying wish, the bereaved prince despatched three ambassadors to Kublai’s Court to seek for him a fitting bride. The Great Khan received them with all honour and hospitality, and then sent for the lady Kukachiu, a maiden of seventeen, and a very beautiful and gracious person. On her arrival at Court she was presented to the three ambassadors, who declared that the lady pleased them well. The overland route from Peking to Tabriz was long and dangerous, and the envoys decided, therefore, on returning, with their fair charge, by sea. While sojourning at the Khan’s Court they had made the acquaintance of the three Venetians, and being greatly impressed by their marvellous good sense and experience, and by Marco Polo’s extensive knowledge of the Indian seas and territories, they entreated the Khan to allow them the advantage and protection of their company. It was with profound reluctance that Kublai gave his consent; but when once he had done so, he behaved with his wonted splendour of generosity. Summoning the three Venetians to his presence, he placed in their hands two golden “tablets of authority,” which secured them a free passage through all his dominions, and unlimited supplies of all necessaries for themselves and for their company. He entrusted them also with messages to the King of France, the King of England, the King of Spain, and other sovereigns of Christendom. Then he caused thirteen ships to be equipped, each with four masts and nine to twelve sails; and when all was ready, the ambassadors and the lady, with the three Venetians, took leave of the Great Khan, and went on board their ships, with a large retinue, and with two years’ supplies provided by the Emperor (A.D. 1292).