Final answer:
The Ottoman Empire lasted for 624 years, from its founding in 1299 to its end in 1922, when the Republic of Turkey was founded. The caliphate was officially abolished in 1924.
Step-by-step explanation:
The Ottoman Empire lasted for 624 years. It was established in 1299, when Osman I began to reign, and eventually came to replace the Abbasids as the leaders of the Muslim world. The Ottomans made significant expansions under various leaders, with notable growth during the reigns of Murat II from 1421-1451, Mehmet II and Selim I from 1451-1520, and reaching its zenith under Suleiman the Magnificent from 1520-1566. Despite experiencing a period of decline after Suleiman's rule, due to various factors including military setbacks and government issues, it remained until 1922 when the Republic of Turkey was founded following World War I, with the caliphate formally abolished in 1924.