the Khyber Pass under Nasrollah Qoli while he gathered 10,000 chosen light cavalry under his direct command. Beginning an epic flank-march of over 80 kilometres through some of the most unnavigable terrain in Asia Nader reached Ali-Masjed whence the 10,000 curved their route of march northwards and onto the eastern end of the Kheibar pass. The abrupt emergence of a strong body of cavalry in their rear caught the governor's forces in a difficult position, though they managed to resist for a short while before Nader's light cavalry routed them entirely. Thus, the path to the north-lands of the Mughal Empire was cleared and the main body of the Imperial Persian army could march into the Mughal interior. On 16 November 1739, Nader marched his advance guard out of Peshawar heading south towards Sindh river in Punjab. Upon crossing the river the Persian army fell upon the defenceless countryside on its way to Lahor pillaging and burning as they went. The governor of Lahor began augmenting his battlements in the hope of resistance. Nader hastened his advance and attacked from an unexpected direction with such force that after a mere day had passed, the governor surrendered to the Shah's will. The gift of two million rupees to the Shah secured the governor in his position as ruler of Lahor. Muhammad Shah gathers a large force The news of the series of conquests by Nader's invading army had caused much consternation at the Mughal court of Muhammad Shah residing in Delhi. Nizam-ul-Mulk was summoned to the Emperor's presence and many summons were sent out across northern India for contribution of military forces. 13 December saw the Mughal army march out of Delhi to confront the invading forces to the north. The enormity of its size was such that the length of the column was 25 kilometres and the width was 3 kilometres. Muhammad Shah himself joined this army. Due to the cumbersome size of the Mughal army, Muhammad Shah could not take his forces any further than Karnal, approximately 120 kilometres north of Delhi. In total, Muhammad Shah commanded a war-camp of 300,000 troops including the non-combatants equipped with 3,000 guns along with 2,000 war elephants. Out these the forces deployed on the field were numbered at 75,000. Despite the large numbers at the Mughal's disposal they suffered from obsolescent war material and antiquated tactical systems. Almost all of the guns