The Balkan Wars
At the far side of Europe, the Hunyadis and the Ottomans continued to struggle over the Balkans. John I Hunyadi had presided at first over an era of relative peace, while Sultan Bayezid concentrated on throwing the Venetians out of Greece and fending off the Persians, and Selim I crushed the Mamluks. But in 1520, Suleiman, later known as the Lawmaker, came to the Ottoman throne, and looked north once more. In 1521, he occupied Bosnia and attacked Belgrade, from which he was thrown back as Mehmet the Conquerer had been decades before.
The invasion came as a welcome relief for John I. Having spent his reign so far consolidating his rule, over both his subjects and his regents, he was politically and financially deeply in debt, effectively blackmailed by his cripplingly expensive Black Army. The only way he could sustain their wages and the comfort of his nobles was through the bounty of war; Suleiman’s invasion was the perfect invitation.
The wars that followed occurred in three phases. In the 1520s, John the Iron halted and reversed the attacks by Suleiman. He retook Bosnia, Wallachia and Bulgaria, launched raids that came within a few hundred miles of Constantinople, supported Venetian reconquest of the Morea, liberated Albania, and even landed an army to support rebels in Pontus. In 1529, a Venetian-Neapolitan-Hungarian army ransacked the cities of Egypt, bringing back immense wealth, along with many bodies. These wars refilled the coffers of Hungary, but dangerously depleted its manpower, and after a ten year respite (in which Suleiman constructed an immense fleet and smashed the naval might of the allies, taking Cyprus, Rhodes, Crete, and the Morea), the Turks forced their way back into Europe in the 1540s, reaching as far as the Carpathians. By this time, John had died, and Matthias the Timid was in power. In 1547, Suleiman finally took Belgrade, and instantly beseiged and took Budapest itself.
The third phase of the war began in theory in 1545, when the Pope declared a holy crusade against the Turks, but did not really take effect until the death of Matthias and the accession of his young son, John II the Crusader, in 1551. John regrouped his forces and used the assistance of his allies – in particular, crusading nobles from France-England and from the domains of the Vaudémonts – to turn the tide once more. Hungarians and Germans fought their way south, while French and Italians crossed from Naples and fought east. The crusading forces were able to reach Salonika briefly, and more permanently establish kingdoms in Greece, but the Hungarians could never penetrate the Balkan Mountains. As the frenzy of the crusade died down, Suleiman gradually reclaimed all of Greece and Albania except for the small Kingdom of Arta, held by the Duke of Bourbon.
In 1566, Suleiman died, and Ottoman policy shifted. The new rulers, first Selim II and then Murad III, were far weaker, giving up more power to their viziers and concubines; the de facto Sultans for the next fourty years were a pair of Venetian women, Cecilia Venier-Baffo and her younger cousin Sofia Baffo. Together, they shaped a more pro-Venetian foreign policy, establishing peace in the West and concentrating on securing their borders in the East against Persia. There were some exceptions to this: Cecilia’s campaign to regain eastern Wallachia and re-establish controll over Moldavia, and her support of a Venetian annexation of Arta. Beyond this, considerable war at sea continued, mostly against Genoa, Aragon-Naples, and France.
After the death of Cecilia, Sofia’s regime launched a five-year war against Hungary that reclaimed Wallachia, and Serbia above Belgrade; an assault on Belgrade was called off when the new king, John the Infidel, agreed sweeping terms. The two powers remained at peace for half a century.