Ghurid invasion of Bengal
The Ghurid invasion of Bengal, commonly known as Muhammad Bakhtiyar Khalji's conquest of Bengal, in 1202 or 1204/5, was a military campaign of Ghurid dynasty led by Muhammad Bakhtiyar Khalji against the Sena dynasty. Muhammad Bakhtiyar Khalji emerged victorious in his campaign at the Sena capital, Nabadwip. He established his kingdom at Lakhnauti which included a small part of Varendra. Following their defeat, Lakshmana Sena, the eighty years old ruler of the Sena dynasty, retreated to the southeastern region of Bengal.
Background
Bakhtiyar Khalji, after the successful annexation of Bihar to the Ghurid dynasty, learned about the Sena Dynasty and its illustrious ruler, Lakshmana Sena. Despite Sena's advanced age and reputation, Khalji was determined to extend his conquests further into Bengal. Upon hearing of Khalji's intent to invade Bengal, many Brahmins and traders decided to leave the Sena capital in search of safer locations. However, in a display of resilience, Lakshmana Sena chose to remain in Nadiya, ready to defend his realm.The siege
Bakhtiyar, leading his forces from Bihar, strategically positioned the majority of his army within a forest near the city of Nadia. It was said that he advanced so rapidly that only 18 horsemen from his army could keep up. Posing as horse traders, the small horde entered the city unchallenged and cautiously towards the palace. Upon reaching the palace, Bakhtiyar initiated an attack on the guards, causing a significant commotion. Then Lakshmana Sena was taking his mid day meal. He took the emperor and his army by shock. Before Lakshmana Sena could react, Bakhtiyar entered the palace, killed some of the guards causing Lakshmana Sena to flee with his retainers to East Bengal leaving his wives and servants on the hand of Bakhtiyar's army. As Bakhtiyar took the possession of the city, his men seized several horses and elephants along with enormous wealth. In the meantime, the main army had entered Bengal. However, Bakhtiyar didn't subjugate the whole of Bengal. He then moved on to Lakhnauti, which he planned to make his capital.Aftermath
Bakhtiyar Khilji left Nadia in ruins and established his capital at Lakhnauti. Lakshmana Sena continued to rule in Eastern Bengal approximately for three or four years after the raid on Nadia and died some time after 1205 A.D. According to the historical work Tabaqat-i Nasiri, Bang was ruled by the descendants of Lakshmana Sena at least up to 1245 A.D. or 1260 A.D.In the year 1204-5, Bakhtiyar Khalji struck a gold coin in the name of his overlord in Delhi, sultan Muhammad of Ghor, with one side depicting a cavalryman charging at full gallop and holding a mace in hand. The coin bears the conquest of Gaur. In 1205, Bakhtiyar Khalji was killed by one of his nobles, Ali Mardan Khalji. During the reign of Ali Mardan Khalji, who declared his independence from Delhi Sultanate, silver coins were struck, commemorating the conquest of Bengal in Ramzan 600 A.H.