Demir Yaman Candar Bey who was the founder of this principality is from the Kayi tribe of Oguz people. Since the period of Isfendiyar Bey who was the 8th Bey of this principality, the dynasty was named as Isfendiyarogullari (since 1392).
The real name of the principality was Candarogullari Principality. But there are some historians that name this dynasty as Kızıl-Ahmedlular according to their last ruler.
Candarogullari had been an important principality in respect of their permanent existence and their extremely close relationship with the Ottomans.
They had dominated for 170 years between the years of 1291-1461. The most long-lasting Turkmen principality is Candarlilar together with the Dulkadirogullari principality following Karamanogullari principality. Candarogullari had been submissive to Seljuk State until the year of 1308 and then to Ilhanli State until the year of 1335. Since this date, they had become independent until the year of 1383. Then, they had subdued to the domination of Osmanoglu Murad I in the year of 1383. They had been ordinary Ottoman governors for 10 years between the years of 1392 and 1402. They had acquired their independence after the calamity in Ankara, but they had subdued to the Ottoman domination again in the year of 1413. This submission gradually increased in the year of 1417 and in the following years. They had been the Ottoman governors again between the years of 1459-1461. The blood relationship between the Osmanogullari and Candarogullari principalities was so mixed that Candarogullari principality did rarely follow an opponent policy againt the Ottomans. They mostly acted in alliance with them and several Candaroğlu people had been directly in the service of Ottomans.
This principality had established dominion in the provinces of Kastamonu, Sinop, Samsun, Cankırı, and Zonguldak. They had established a close relationship through relatives in the Ottoman palace. This principality was annexed to the Ottoman State in the year of 1461.
Giyaseddin Mesud II who was the sultan of Turkey Seljuk State had been taken prisoner in a war in which Cobanogullari principality was involved the course of the struggles for the sovereignty, but he was saved then (1292). Sultan Mesud had given Katamonu and its environs to Semseddîn Demir Yaman Candâr who had provided help in the course of the rescue of the sultan. Thus, this principality was founded.
But it was no use since Kastamonu was under the dominion of Husameddin Bey from Cobanogullari principality. Suleyman Pasha who was Semseddin Yaman Candars son replaced him and he conquered Kastamonu with a sudden attack. Then, the city of Sinop was annexed to the lands of Candarogullari principality (1322). After a while, we have observed that this principality was divided into two branches due to the struggles for the sovereignty. Suleyman-shah had established dominion in Kastamonu through the support of Ottomans since the year of 1384, and his rival, Celaleddin Bayezid had to retreat to Sinop.
Although Suleyman-shah II had established friendly relationship with Ottomans, this friendship could only last until the first years of Yıldırım Bayezid. Yıldırım Bayezid had captured the lands of Candarogullari principality in the course of his activities in order to establish the Turkish union in Anatolia, but the Candarogullari principality in Sinop had maintained its existence. Pursuant to Ankara War (1402), Isfendiyar Bey recognised the domination of Timur. In return to this recognition, the older lands of Candarogullari principality were given back to him, and he restablished dominion in Kastamonu.
followed a prudent policy in the course of the struggles for sovereignty among the Ottoman princes, and he supported each of them on different occasions. He had good relationship with Celebi Mehmed who was the winner of these struggles. He had spent reserve forces under the command of his son, Kasim Bey in the course of the military expeditions organised by Celebi Mehmed to Karaman and Eflak (1417).
But Kasim bey did not return, and wanted Celebi Mehmet to give back some of the regions of Candarogullari principality to him. As a result, Kasim Bey attained this desire, and Isfendiyar Bey had remained submissive to Ottomans. However, Isfendiyar Bey benefited from the turmoils that resulted from the enthronement of Sultan Murad II that ascended the throne of Ottomans (1421) and he recaptured the lands under the domination of Kasim Bey.
Murad II suppressed the rebellions of the princes and established the public order. Then, he advanced against Isfendiyar Bey. Isfendiyar Bey became submissive to the Ottomans again (1423-24) and he established good friendship with them from that time on.
Candarogullari Principality preserved their existence until the period of Fatih Sultan Mehmed. While Fatih returned from his expedition to Trebizond, he annexed Kastamonu and Sinop to the lands of Ottomans and the Candarogullari principality was abolished thereof (1462).
Candarogullari beys had improved their countries with various works of art. The most significant works pertaining to this period that attract attention are the mosque of Ibn Neccar Camii located in Kastamonu and the charitable establishment of Ismail Bey Imareti that is a complex of buildings composed of six structures. Candarogullari beys had also protected the artists and had them write several Turkish works in their name. Ismail Bey from Candarli principality (1443-1461) had written a great masterpiece titled as Hulviyât-ı Şâhî.