The suppression of rebellion in Asia Minor, the subjection of the Greek Emperor to the position of a humble vassal, and the capture of Salonika had occupied Murad for some years. Later he was involved in long struggles with his neighbours, the Hungarians, on the northern boundaries of his Empire. The Ottomans were engaged in constant raids across the Danube, where vast districts were devastated, and thousands of their population were carried off as captives for sale as slaves. There arose about this time in Hungary a national hero, the celebrated Hunyadi, a natural son of the late King Sigismund. He was a born leader of men, not a great general, but a most valiant fighter. He had gained great distinction in war in other directions. He now became the soul of hostility against the Ottomans. He was known as the White Knight, on account of his silver armour, which always shone in the van of the impetuous charges of his cavalry. He was rightly regarded by his countrymen as a patriot and a national hero. None the less, he was a bloodthirsty ruffian. He made a practice of massacring all the prisoners taken in battle. He found pleasure in having this effected, in his presence, at banquets, where the guests were entertained by the shrieks of the dying men.
Hunyadi for twenty years was a terror to the Ottoman armies. His first encounter with them was at Hermannstadt, north of the Danube, which was invested by an army of eighty thousand Ottomans. He led an army of twenty thousand Hungarians against them, in relief of the fortress, and inflicted a severe defeat on them, in despite of great disparity of numbers. Twenty thousand of the Ottomans were killed, including the general. The others were dispersed. Murad sent another army of eighty thousand men against him, under another Pasha. Hunyadi again defeated it with great slaughter at Varsag.
These notable victories roused great enthusiasm in Europe. It was determined to take the offensive against the Ottomans, and to make another effort to drive them out of Europe. A coalition was formed for the purpose between Hungary and Poland, then united under King Ladislaus, and Wallachia and Bosnia. Serbia, which under its king, Stephen Lazariwitch, had been the firm ally of the Ottomans, and had supported them in many campaigns in Asia and Europe, was now induced to abandon this alliance and, under Stephen’s successor, George Brancowitch, to join the confederacy against the Ottomans. The Pope, Eugenius, was most active in support of this combination. His legate, Cardinal Julian Cesarini, led an armed force in support of it. Money was raised for the purpose of the war by a great sale of indulgences to the faithful in every part of Europe. A large contingent of French and German knights joined the allied army. It was, in fact, another crusade, prompted by religious zeal on behalf of Christianity against Islam. The allied army was under the nominal command of Ladislaus, but Hunyadi was its real leader.
The Republics of Venice and Genoa gave their support, and as, at this time, the Ottomans had no naval force, it was hoped that these Powers, by means of their numerous and powerful galleys, would prevent the transfer to Europe of Murad’s main army, which was again engaged in conflict with the Karamanians in Asia Minor.
The allied army, under these favourable circumstances, crossed the Danube in 1443. It defeated an Ottoman army on the banks of the Masova and again at Nisch. It then crossed the Balkan range in winter—an operation of extreme difficulty, which has since only twice been effected, by General Diebitsch and General Gourko—and again defeated the Turks in a battle at the foot of these mountains. Strange to say, instead of marching onwards to Adrianople, as Diebitsch did in 1829, Hunyadi was content with the laurels already achieved, and returned with his army to Buda, where he displayed his trophies and received a triumph.
Murad, on hearing of the retreat of the Hungarians across the Balkans, determined to come to terms with them, and not to pursue them again across the Danube. With some difficulty, and in spite of the sullen opposition of Cardinal Julian and the French contingent, a treaty was agreed to, at Szegeddin, with Ladislaus, by which Serbia was to be freed from dependence on the Ottoman Empire and Wallachia was to be ceded to Hungary. The treaty was to be in force for ten years. It was solemnly sworn to on the Gospel and the Koran by Ladislaus and Murad.
While this treaty was being negotiated Murad, weary of war, and desirous of spending the remainder of his life in sensual enjoyments which had so long been denied to him, decided to abdicate his throne. He was still in the full vigour of life at the age of forty-one, though he was said to be growing rather fat. He did not propose, like the Emperor Charles V, to retire to a monastery, but rather, like Diocletian the Roman Emperor, to a luxurious palace, surrounded by beautiful gardens, which he had prepared for his retreat at Magnesia. On the ratification of the treaty of Szegeddin, in 1444, he carried out this purpose, and his son Mahomet, at the age of fourteen, was proclaimed Sultan in his place.
When this became known to the Hungarians a revulsion of opinion took place against the recent treaty with the Turks. The Hungarian Diet determined, at the instance of Cardinal Julian, backed up by the Pope, to break the treaty. News had arrived of a fresh outbreak of the Karamanians. The fleets of Genoa, Venice, and Burgundy were masters of the Hellespont and would, it was believed, prevent the Ottoman army in Asia Minor from crossing into Europe. The opportunity for crushing the Turks and driving them out of Europe seemed to be most favourable.
Is it now [said Cardinal Julian to the Hungarian Diet] that you will desert expectations and your own fortunes? Is it to your God and your fellow-Christians that you have pledged your faith? That prior obligation annihilates a rash and sacrilegious oath to the enemies of Christ. His vicar on earth is the Roman Pontiff, without whose sanction you can neither promise nor perform. In his name I absolve your perjury and sanctify your arms. Follow my footsteps in the path of glory and salvation; and, if you still have scruples, devolve on my head the punishment and the sin.