Answer
In 1808, Selim III, the Ottoman Sultan known for his reformist policies, was assassinated by a group of rebellious janissaries during the Auspicious Incident. The janissaries, a powerful military unit within the Ottoman Empire, opposed Selim III's modernization efforts, which aimed to strengthen the central government and limit their influence. His death marked a significant setback to the reform movement and contributed to the decline of the Ottoman Empire.