If Marco had been consulted in the choice of his immediate ancestry, he could not have done better than fortune served him in the person of his father, Nicolo Polo, who was a nobleman and a merchant of Venice. He was a traveller prior to the birth of his son, for just previous to that event, which occurred nearly two hundred years before Amerigo Vespucci was born, he and his brother set out for Constantinople. Thence they went into Armenia, and around the south coast of the Caspian Sea to Bokhara, where they met some Persian envoys who were bound for Cathay, or China, and who persuaded them to go along. At Peking, it is supposed, they met the great and powerful Kublai Khan, Emperor of the Mongols, and Tartars, who received them kindly and at whose court they remained a year. They were the first Europeans he had ever seen, and such was his interest in their stories of strange peoples and governments that he commissioned them as envoys to the pope, giving them letters in which he expressed his desire that Europeans learned in the arts and sciences should be sent for the instruction of his people. Then they were reluctantly dismissed, with gifts of gold and spices, and after many perilous adventures finally reached their home in Venice. They had been gone almost ten years, and when Nicolo Polo first saw his son, on his return to Venice, Marco was a youth at school, well advanced in his studies. Two years later, when Marco was about twelve, the three Polos set out on their return to Cathay, accompanied by two friars, who were "endowed with ample powers and privileges, the authority to ordain priests and bishops, and to grant absolution in all cases, as fully as if the pope were personally present." They took with them rich presents for the khan, including a bottle of precious oil from the holy sepulchre in Jerusalem, which was supposed to possess miraculous virtues. The journey was commenced in or about the year 1271, but, owing to innumerable and vexatious delays on the way, the Polos did not reach the court of the grand khan until the spring of 1275. They were more than three years in making the journey, but in spite of difficulties and dangers these remarkable men persisted until the object of their travels was accomplished. The friars had become alarmed at the prospect of peril to themselves, and early in the undertaking beat a retreat to Acre, so the three Venetians alone arrived at Chambalu, and delivered to the grand khan the letters and presents from the pope. They were received with extreme cordiality by the khan, who was especially pleased with young Marco, and accepted the presents with delight, the holy oil from Jerusalem being reverently cherished.