Salimgarh Fort (Hindi: सलिमगर खिला, Urdu: سلیم گڑھ ،literally "Salim’s Fort") was built in 1546 AD, in Delhi, in a former island of the Yamuna River, by Salim Shah Suri, son of Sher Shah Suri. There was a pause in Mughal rule when in 1540 AD Sher Shah Suri defeated the Mughal Emperor Humayun (and ousted him from Delhi) and established the Sur dynasty rule in Delhi. Sur dynasty rule lasted till 1555 AD when Humayun regained his kingdom by defeating Sikander Suri, the last ruler of the dynasty. During the Mughal period, in later years, while building the Red Fort and Shahjahanbad, several Mughal rulers including Emperor Shahjahan who is credited with completing Shahjahanabad in 1639 AD had camped at this fort. It is said that Humayun had camped at this fort for three days before launching his successful attack for recapturing Delhi.

Aurangzeb, the Mughal Emperor, converted the fort into a prison, which practice was perpetuated by the British who took control of the fort in 1857. The Fort is part of the Red Fort Complex. The complex was declared as a UNESCO World Heritage site in 2007, which obligates Archeological Survey of India (ASl) to ensure well planned conservation measures for the heritage monuments.

Sher Shah Suri (1486 – May 22, 1545) (Pashto: فريد خان شیر شاہ سوری - Šīr Šāh Sūrī, Bengali: শের শাহ সুরি), birth name Farid Khan, also known as Sher Khan (The Lion King), was the founder of the Muslim Sur Empire in northern India, with its capital at Delhi. An Afghan (Pathan) by origin, he rebelled against the Mughals and took control of India in 1540 until an accidental death in 1545 when Islam Shah Suri became his successor. He first served as a private before rising to become a commander in the Mughal Army under Babur and then as the governor of Bihar. In 1537, when Babur's son Humayun was elsewhere on an expedition, Sher Khan, power hungry turned on his true master and overran the state of Bengal and established the Sur Empire. A brilliant strategist, Sher Shah proved himself a gifted administrator as well as an able general. His reorganization of the empire laid the foundations for the later Mughal emperors, notably Akbar the Great, son of Humayun.

During his five year rule from 1540 to 1545, he set up a new template for civic and military administration, issued the first Rupee and re-organised the postal system of India. He further developed Humayun's Dina-panah city and named it Shergarh and revived the historical city of Pataliputra as Patna which had been in decline since the 7th century CE. He is also famously remembered for killing a fully grown tiger with his bare hands in a jungle of Bihar.

His Highness, The Imperial Prince (Shahzada) Dara Shukoh (Persian: دارا شكوه ‎) (full name and royal title Padshahzada-i-Buzurg Martaba, Jalal ul-Kadir, Sultan Muhammad Dara Shukoh, Shah-i-Buland Iqbal) (March 20, 1615 – August 30, 1659) was the eldest son and the heir apparent of Mughal Emperor Shah Jahan and his wife Mumtaz Mahal. His name دارا شكوه in Persian means "Darius the Magnificent". He was favoured as a successor by his father and his sister Princess Jahanara Begum Sahib, but was defeated by his younger brother Prince Muhiuddin (later the Emperor Aurangzeb) in a bitter struggle for the imperial throne. The course of the history of the Indian subcontinent, had Dara prevailed over Aurangzeb, has been a matter of some conjecture among historians.

Dara was born near Ajmer on 20 March 1615, the eldest son of Prince Shahab ud-din Muhammad Khurram (Shah Jahan) and his second wife, Mumtaz Mahal. When he was 12, his grandfather, Emperor Jahangir, died, and his father succeeded as emperor.