war with Mughal Subedars, and the hit-and-run tactics of the Sikh warriors caused devastation. In Ajmer, Ajit Singh carved out a vast territory and allied himself with the renegade Marathas. While in the Deccan the Marathas had ruined Mughal fortifications and were already on the warpath. All this greatly contributed to the decline of the Mughal Empire. In 1737, the Marathas under Baji Rao I annexed Gujarat, Malwa and Bundelkhand, and raided the Mughal capital Delhi. In 1739, Nader Shah of Persia, lured by the wealth and weakness of the Mughals, took advantage of a rebellion on his eastern borders near Kandahar and initiated a campaign against the Mughal Empire capturing Ghazni, Kabul, Lahore, and Sindh. He then advanced against Muhammad Shah and defeated him at the Battle of Karnal. Rao Bal Kishan, with his army and with the forces of Delhi, fought Nadir Shah. His army included 5000 infantry and 2000 cavalry. Rao Bal Kishan was killed in the battle but immortalized the name "Vijay or Veergati" The Battle was ambitious as Nadir Shah itself remarked to Mughal Emperor that if your combined forces helped Rao Balkrishna of Rewari, than I might not able to enter in Delhi. I had never seen any warrior like him brave , Fierce and strong. After this to a royal chhatri kiosk was made by Mughal Emperor to remark tribute to Rao Balkrishna. Today also the Chhatri is in Karnal. In 1748, Ahmad Shah Durrani of Afghanistan invaded the Mughal Empire. Heir apparent Ahmad Shah Bahadur, Grand Vizier Qamaruddin Khan and his son Moin-ul-Mulk better known as Mir Mannu, Intizam-ud-Daula and Safdarjung were sent with 75,000 men after the defeat of Shahnawaz Khan in Lahore. At the Battle of Manupur (1748), Durrani's 12,000 men were defeated, and he was forced to retreat. There was a great rejoicing for this event throughout the Mughal Empire. Cultural developments While Urdu (derived from Zuban-i Urdū-yi Muʿallá or in local translation Lashkari Zaban, shortened to Lashkari) was already in use before Muhammad Shah's reign, it was during his reign that it became more popular among the people and he declared it as the court language, replacing Persian. During Muhammad Shah's reign, Qawwali was reintroduced into the Mughal imperial court and it quickly spread throughout South Asia. Muhammad Shah is also known to have introduced religious institutions for education such as Maktabs. During his reign, the Quran was