The talents and energy with which he was endowed had endeared him to the people, and great hopes were founded on his accession. He had associated much with foreigners, and was thoroughly persuaded of the necessity of reforming his state. But Austria and Russia gave him no time for anything but defence, and it was not until the peace of Jassy (1792) that a breathing space was allowed him in Europe, while Bonaparte's invasion of Egypt and Syria soon called for Turkey's strongest efforts and for the time shattered the old-standing French alliance.
Selim profited by the respite to abolish the military tenure of fiefs; he introduced salutary reforms into the administration, especially in the fiscal department, sought by well-considered plans to extend the spread of education, and engaged foreign officers as instructors, by whom a small corps of new troops called nizam-i-jedid were collected and drilled. So well were these troops organized that they were able to hold their own against rebellious Janissaries in the European provinces, where disaffected governors made no scruple of attempting to make use of them against the reforming sultan.
Emboldened by this success, Selim issued an order that in future picked men should be taken annually from the Janissaries to serve in their ranks. Hereupon the Janissaries and other enemies of progress rose at Adrianople, and in view of their number, exceeding 10,000, and the violence of their opposition, it was decided that the reforms must be given up for the present. Serbia, Egypt and the principalities were successively the scene of hostilities in which Turkey gained no successes, and in 1807 a British fleet appeared at Constantinople, strange to say to insist on Turkey's yielding to Russia's demands besides dismissing the ambassador of Napoleon I.
Selim was, however, thoroughly under the influence of this ambassador, Sebastiani, and the fleet was compelled to retire without effecting its purpose. But the anarchy, manifest or latent, existing throughout the provinces proved too great for Selim to cone with. The Janissaries rose once more in revolt, induced the Sheikhul-Islam to grant a fetva against the reforms, dethroned and imprisoned Selim (1807), and placed his nephew Mustafa on the throne.
The pasha of Rustchuk, Mustafa Bairakdar, a strong partisan of the reforms, now collected an army of 40,000 men and marched on Constantinople with the purpose of reinstating Selim. But he came too late; the ill-fated reforming sultan had been strangled in the seraglio, and Bairakdar's only resource was to wreak his vengeance on Mustafa and to place on the throne Mahmud II, the sole surviving member of the house of Osman.