| Yakub II | |
|---|---|
| Bey of Germiyan | |
| First reign | 1387–1390 |
| Predecessor | Suleiman Shah |
| Successor | Occupation by Bayezid I of the Ottoman Sultanate |
| Second reign | 1402–1411 |
| Predecessor | Sari Timurtash Pasha (Ottoman beylerbey of Anatolia) |
| Successor | Occupation by Mehmed II of Karaman |
| Third reign | 1414–1429 |
| Predecessor | Occupation by Mehmed II of Karaman |
| Successor | Bequest to Murad II |
| Died | January 1429 Kütahya, Germiyan |
| Spouse | Pasha Kerime Hatun |
| Dynasty | Germiyan |
| Father | Suleiman Shah |
| Mother | Daughter of Umur of Aydın |
| Religion | Islam |
Yakub II (died January 1429), also known as Yakub Chelebi, was Bey of Germiyan in western Anatolia from 1387 to 1390, 1402 to 1411, and 1414 until his death. Yakub was the patron of several literary and architectural works produced during his reign.
He was initially on friendly terms with the Ottomans, but turned against Sultan Bayezid I (r. 1389–1402) and attempted to reclaim considerable territory, including the former capital Kütahya. He was jailed by Bayezid in 1390, and Germiyan wholly came under Ottoman control. Nine years later, Yakub escaped from prison and sought the protection of Timur (r. 1370–1405), who, after crushing Bayezid with the help of Yakub at the Battle of Ankara in 1402, restored Germiyan's former boundaries. In 1411, Kütahya fell to Mehmed II of Karaman (r. 1398–99, 1402–20), interrupting Yakub's reign a second time. His rule was reinstated by the Ottoman sultan, Mehmed I (r. 1413–21), upon the defeat of the Karamanids. Although Yakub initially supported Mustafa Chelebi as a claimant to the Ottoman throne, Mustafa's defeat forced Yakub to have amicable relations with Sultan Murad II (r. 1421–44, 1446–51). Yakub did not have any male heirs and left the rule to Murad II in his will shortly before he died in 1429.