By the early 17th century, the Janissary corps had ceased to function as an elite military force, and had become a privileged hereditary class, and their exemption from paying taxes made them highly unfavorable in the eyes of the rest of the population. The number of Janissaries grew from 20,000 in 1575 to 135,000 in 1826, about 250 years later.^[37] Many were not soldiers but still collected pay from the empire, as dictated by the corps since it held an effective veto over the state and contributed to the steady decline of the Ottoman Empire. Any sultan who tried to diminish its status or power was immediately either killed or deposed. As opportunities and power continued to rise within the Janissary corps, it began to undermine the empire. Over time it became clear that for the empire to restore its position as a major power of Europe, it needed to replace the Janissary corps with a modern army.

When Mahmud II began forming a new army and hiring European gunners, the Janissaries mutinied and fought on the streets of the Ottoman capital, but the militarily superior Sipahis charged and forced them back into their barracks. Turkish historians claim that the counter-Janissary force, which was great in numbers, included the local residents who had hated the Janissaries for years.

The sultan informed them that he was forming a new army, the Sekban-ı Cedit, organized and trained along modern European lines (and that the new army would be Turkish-dominated). The Janissaries saw their institution as crucial to the well-being of the Ottoman Empire, especially to Rumelia, and had previously decided they would never allow its dissolution. Thus, as predicted, they mutinied, advancing on the sultan's palace. Mahmud II then brought out the Holy Banner of the Prophet Muhammad from inside the Sacred Trust, intending all true believers to gather beneath it and thus bolster opposition to the Janissaries.^[38] In the ensuing fight the Janissary barracks were set ablaze by artillery fire, resulting in 4,000 Janissary deaths; more were killed in the heavy fighting on the streets of Constantinople. The survivors either fled or were imprisoned, their possessions confiscated by the Sultan. By the end of 1826 the captured Janissaries, constituting the remainder of the force, were put to death by decapitation in the Thessaloniki fort that soon came to be called the "Blood Tower". The Janissary leaders were executed and their possessions confiscated by the Sultan. The younger Janissaries were either exiled or imprisoned. Thousands of Janissaries had been killed, and thus the elite order came to its end. A new modern corps, Asakir-i Mansure-i Muhammediye ("The Victorious Soldiers of Muhammad") was established by Mahmud II to guard the Sultan and replace the Janissaries.