Mirza Muhammad Siraj-ud-Daulah was the grandson of Nawab Alivardi Khan and son of Amina Begum and Zainuddin Ahmed Khan. He was born in 1733 and soon after his birth Alivardi Khan appointed as the deputy governor of Bihar. So Siraj-ud-Daula was regarded as a "fortune child" in the family and his grandfather had special affection and favour for him. It is stated that Alivardi had given his heart to Siraj ud Daula from the day of his birth and "never kept him apart from himself".