Yakub II

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.

The Germiyans first appeared around Malatya in 1239, under Kaykhusraw II's rule (r. 1237–46) of the Sultanate of Rum, when they were tasked with subduing Baba Ishak.

While Karaman seized Beyşehir, Yakub started capturing some of the former possessions of Germiyan that his father had given to the Ottomans as part of Devletşah Hatun's dowry.

Before returning to Anatolia from the Balkans, Bayezid first ensured stability in the latter region by making peace with Serbia and concluding internal conflicts within the Byzantine Empire in his favor.

Intimidated by Bayezid's seizure of Saruhan, Aydın, and Menteshe, Yakub attempted to return to good terms with him through various gifts but was nevertheless imprisoned and kept in the castle of Ipsala.

[5] Yakub sought the protection of Timur (r. 1370–1405) in 1399, having escaped from prison and traveled to Syria in disguise through the Mediterranean Sea presumably the same year.

Timur stayed in Kütahya for some time, subjecting the inhabitants to a one-time tax and confiscating the treasury of Sari Timurtash Pasha.

This escalated to a war between the two in September 1410, and Kütahya fell to Mehmed II of Karaman (r. 1398–99, 1402–20) the next year, which effectively ended Yakub's second reign.

When Musa's remains were brought to Bursa, signaling the defeat, Mehmed II of Karaman retreated in a hurry and left the territories he had taken from Germiyan.

Murad's younger brother and governor of Hamid, Mustafa Chelebi was sponsored by Yakub, Karaman, and the Turghudlu tribe of Turkmens as a claimant to the Ottoman throne.

Mustafa besieged and gained control of Iznik, and declared himself ruler, taking advantage of Murad's investment in the Siege of Constantinople (1422).

It was later destroyed and the building was restored in accordance with its original form by its waqf (endowment) trustee Ishak Fakih bin Halil in 1440–41.

The tomb includes the sarcophagi of Yakub II and his wife Pasha Kerime Hatun, which are ornamented with encaustic tiles.