Final answer:
Various ethnic groups revolted against the Ottoman Empire for reasons such as nationalism and a desire for independence. Examples include the Greeks and the Arabs.
Step-by-step explanation:
In the early nineteenth century, various ethnic groups revolted against the Ottoman Empire. One example is Greece, which had been under Ottoman rule for centuries. The Greeks, along with other Balkan peoples, were inspired by the ideology of nationalism and sought to establish their own independent states.
Another example is the Arab Revolt of 1916, led by Arab Muslims against the Ottoman Empire. The revolt aimed to gain independence for Arab territories, and it received support from the British government.
The decline of the Ottoman Empire and its weakening control over its territories led to revolts and resistance movements in different parts of the empire, such as Egypt and Ethiopia.