The Ottoman Empire's Worst Defeats

In the wake of taking Constantinople, the Ottoman Empire would spend the next few centuries expanding its size, power, and influence, bumping up against Eastern Europe and becoming one of the world's most important geopolitical players. It was a rise that would not truly start to wane until the 19th century. The long agony of the "sick man of Europe," an expression used by the Tsar of Russia to depict the falling Ottoman Empire, could almost blind people to its incredible power and history. Preserving its mixed heritage, coming from both its geographic position rising above the ashes of the Byzantine Empire and the tradition inherited from the Muslim Conquests, the Ottoman Empire lasted more than six centuries. Its soldiers fought, died, and conquered lands on three different continents, making it one of the few stable multiethnic empires in history, and likely one of the last. Thus, it's somewhat inevitable that the history of its decline is at the heart of complex geopolitical disputes, as well as sectarian tensions that are still key to understanding the Middle East, North Africa and the Balkans.
When studying the fall of the Ottoman Empire, historians have argued over the breaking point that saw a leading global power slowly become a decadent empire. The defeat in the Battle of Lepanto stopped the Ottomans from pushing further into the Mediterranean, and the Battle of Vienna in 1683 was certainly an important turning point for the expanding empire, as the defeat of Grand Vizier Kara Mustafa Pasha at the hands of a coalition led by the Austrian Habsburg dynasty, Holy Roman Empire and Polish-Lithuanian commonwealth marked the end of Ottoman expansionism. It was also the beginning of a slow decline during which the Ottoman Empire suffered multiple military defeats, found itself mired by corruption, and had to deal with the increasingly mutinous Janissaries (the Empire's initial foot soldiers).