Baldwin set out for the East in the spring of 1203, Marie, who was then laid by in childbed, followed towards the close of the month, but she never saw her husband again. It happened thus. That shrewd old fox, Dandolo of Venice, taking advantage of the poverty of the Crusaders, compelled them to undertake for him a campaign against Zara, by way of payment for their transport to Palestine. Then came the conquest of Constantinople and the founding of the Latin Empire, and the elevation of Baldwin himself to the imperial throne (April 9, 1204). Meanwhile Marie had gone on to Syria and was there awaiting her lord. Presently, with the summer heat, plague swept the land, and Marie herself fell sick. When she was lying at death's door, the news of Baldwin's good fortune reached the town, and it was perhaps in reply to some inquiry of hers as to the cause of his long tarrying, that her attendants informed her that the erst Count of Flanders was now Emperor of Rome, and then the end came. Baldwin was now at the zenith of his glory. From a petty tributary chief of a tribe of semi-barbarians, he had been raised to the throne of a great and civilized empire; but the tide of fortune was soon to turn, and Marie's death was the first drop in the bitter chalice that fate was mingling for him. In less than a year the discontent of the Greeks broke out in open rebellion. Joannice of Bulgaria had promised them help, and with a huge army, reinforced by a horde of Tartars, he laid siege to Adrianople. Baldwin marched to relieve the town, and fell wounded, perhaps slain, before its walls. Of what had actually befallen the Emperor nothing was certainly known. Some of his comrades were sure they had seen his dead body, others were equally sure that he had been taken alive. The Bishop of Soissons set out for France to gather funds for ransom. Henry of Flanders had recourse to the good offices of the Pope, who at once sent an embassy to Joannice to treat for Baldwin's release. Vain request. 'The Emperor,' averred the King of the Bulgarians, 'had paid Nature's debt--_debitum carnis exsoluerat_.'