İsa Çelebi

İsa Çelebi (1380 – 1406) was an Ottoman prince (Turkish: şehzade) and a co-ruler of the empire during the Ottoman Interregnum. The name Çelebi is an honorific title meaning gentleman; see pre-1934 Turkish naming conventions.

İsa was one of the sons of Beyazid I, the Ottoman sultan. His mother was Devletşah Hatun, the daughter of Süleyman Şah of Germiyanids and Mutahhara Abide Hatun bint-i Sultan Veled bin Mawlānā Jalal al-Din Muhammad Rumi. İsa worked as a sanjak governor in Antalya and fought in the Battle of Ankara in 1402 with his father. The Ottoman army was defeated, Beyazid I was captured by Timurlane, and İsa escaped to west Anatolia.

In 1403, after learning about his father's death in captivity, he began to struggle for the vacant throne against his brothers Mehmet Çelebi, Musa Çelebi, and Süleyman Çelebi. He fought against Musa to gain control of Bursa, the Anatolian capital of the empire. He defeated Musa and won control of a part of Anatolian territory of the empire. But the European territory, Rumeli, was under the control of Süleyman and the east part of Anatolian territory was under the control of Mehmet (the future Mehmet I). Feeling his lands to be fragile situated between his brothers' on both sides, he signed a treaty of friendship with the Byzantine emperor Manuel II Palaiologos and refused Mehmet's suggestion to partition the Anatolian part of the empire with him, on the grounds that he was the older brother and was entitled the entirety of the territory. But following this refusal, he was defeated by Mehmet in the Battle of Ulubat in 1405. In this battle, he also lost his vizier Timurtaş, who was an experienced statesman. He escaped to Rumeli over Byzantine territories.

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