himself led a group of 17 horsemen and advanced towards Nadia in the guise of horse-traders. In this manner, Bakhtiyar had no problem in entering through the gates of the city. Shortly afterwards, Bakhityar's main army joined him and within a short while Nadia was captured. After capturing Nadia, Bakhtiyar advanced towards Gauda (Lakhnuti), another major city of the Sena kingdom, conquered it and made it his capital in 1205. In the following year, Bakhtiyar set out on an expedition to capture Tibet, but this attempt failed and he had to return to Bengal in poor health and with a reduced army. Shortly afterwards, he was killed by one of his commanders, Ali Mardan Khilji. In the meantime, Lakshman Sen and his two sons retreated to Vikramapur (in the present-day Munshiganj District in Bangladesh), where their diminished dominion lasted until the late 13th century. Khiljis were Turko Afghan. The period after Bakhtiar Khilji's death in 1207 involved infighting among the Khiljis. This was typical of a pattern of succession struggles and intra-sultanate intrigues during later Turko Afghan regimes. In this case, Ghiyasuddin Iwaj Khilji prevailed and extended the Sultan's domain south to Jessore and made the eastern Bang province a tributary. The capital was established at Lakhnauti on the Ganges near the older Bengal capital of Gaur. He managed to make Kamarupa and Trihut pay tribute to him. But he was later defeated by Shams-ud-Din Iltutmish. Sonargaon Sultanate Fakhruddin Mubarak Shah ruled an independent kingdom in areas that lie within modern-day eastern and south-eastern Bangladesh from 1338 to 1349. He was the first Muslim ruler to conquer Chittagong, the principal port in the Bengal region, in 1340. Fakhruddin's capital was Sonargaon which emerged as the principal city of the region and as the capital of an independent sultanate during his reign. Ibn Batuta, after visiting his capital in 1346, described the Shah as "a distinguished sovereign who loved strangers, particularly the fakirs and Sufis." Bengal Sultanate Ilyas Shahi dynasty Shamsuddin Iliyas Shah founded an independent dynasty that lasted from 1342 to 1487. The dynasty successfully repulsed attempts by Delhi to conquer them. They continued to extend their territory across what is modern-day Bengal, reaching to Khulna in the south and Sylhet in the east. The sultans developed civic institutions and became more responsive and "native" in their outlook and became increasingly independent from Delhi influence and control. Considerable architectural projects