Short answers, pulled from the story.
The Badshahi Mosque was built by the Mughal emperor Aurangzeb, the sixth Mughal emperor. Construction took place between 1671 and 1673, and the mosque opened in 1673 or 1674. Oversight of construction was entrusted to Muzaffar Hussein, also known by his title Fidai Khan Koka, who was Aurangzeb's foster brother and governor of Lahore.
The Badshahi Mosque was built to commemorate Aurangzeb's military campaigns in southern India, and particularly his campaigns against the Maratha ruler Shivaji. Its placement directly across from the Lahore Fort and its Alamgiri Gate, which Aurangzeb built at the same time, underscored its symbolic significance.
The courtyard of the Badshahi Mosque covers 276,000 square feet, paved in sandstone and enclosed by single-aisled arcades. When used as an Idgah, it can accommodate one hundred thousand worshippers. The prayer hall separately holds ten thousand worshippers.
The four octagonal minarets at the corners of the Badshahi Mosque are each 196 feet tall. They are three storeys high, made of red sandstone, with an outer circumference of 67 feet and an inner circumference of 8.5 feet, and each is topped with a marble canopy.
After Ranjit Singh captured Lahore on the 7th of July 1799, the mosque's courtyard was used as a stable for army horses and its eighty study rooms housed soldiers and military stores. During the First Anglo-Sikh War in 1841, Sher Singh placed cannon atop its minarets to bombard the Lahore Fort, and a French officer named Henri de La Rouche stored gunpowder in a tunnel linking the mosque to the fort.
The British formally returned the Badshahi Mosque to the Muslim community in 1856. The handover was made by John Lawrence, the Chief Commissioner of the Punjab Province. The Badshahi Mosque Authority had been established in 1852, with the assistance of Khan Bahadur Nawab Barkat Ali Khan, to oversee restoration and re-establish the mosque as a place of worship.