1- Some people assume that when Mongols devastated Afghanistan in 13[SUP]th[/SUP] century ¸ Pashtuns must have borrowed from them at that occasion. Why would Mongol conquerors bestow their royal title to them?. Also People should keep in mind that Mongols devastated central and northern Afghanistan which was populated by Persians/Tajiks, much of the present day Afghanistan was not inhabited by Pashtuns/Afghans at that time. Pashtuns at that time were confined to Koh Sulieman range and Koh Sufaid range of Hindu Kush as evident from statements of Alberuni of 11[SUP]th[/SUP] century and Ibn-e-batuta of 14[SUP]th[/SUP] century. These mountain ranges were natural barriers/forts , and protected Pashtun tribes from Mongols who were unstoppable on plains. Mongol themselves avoided sending armies in to these mountains. Pashtuns didn’t integrate into Mongol empire and were hostile to them. When Jalaludin Khwarzimi came to Ghazni to assemble a Turkish force , he also invited Afghan/Pashtun tribes from the hills to join his forces , which swelled his army to 60,000. This Turk-Afghan force was the first to inflict first ever defeat on Mongols in 1221 AD at Parwan. After victory, Afghan tribesmen quarreled with Turkish soldiers over spoils of war and deserted Jalaludin. But they kept raiding Mongol garrisons in subsequent years.
2- Due to ferocity and reputation of the Pashtun tribes on Mongol empire’s frontier with India, Turk sultans began to employ them in large numbers and all the forts along Mongol frontier were garrisoned with Afghans as a defense strategy. Earlier Iltumish had used Afghans to counteract rebellious Turkish nobility. The Afghan/Pashtun soldiers of Slave dynasty and Khilji dynasty , on the front lines played an important role in repulsing Mongol invasions of India. Most of the soldiers of Turkish slave dynasty consisted of Khiljis and Afghans. With the ascendancy of Turko-Afghan Khiljis to throne, Pashtuns began to find place in the nobility. For example Malik Inkhtiya-uddin Yal Afghan was a notable Pashtun noble of Khilji empire. Tughlaq also patronized Pashtuns and large number of Pashtuns, along with Mongols, were appointed “sadah” amirs i.e chief of hundred villages. At the time of invasion of Amir timur , the Tuglaq empire was practically controlled by two Afghan brothers Malik Iqbal Khan and Sarang Khan, sons of Zafar Khan Lodhi. After death of last Tughlaq ruler Nasir-ud-din, the nobility of the Tughlaqs appointed Daulat Khan Lodhi , the sipah-e-salar of army, as new Sultan in 1412 who sat on throne for two years and then was defeated and killed by Khizr Khan who founded Sayyid dynasty.
3- Lodis were involved in Indian affairs from very early on . Malik Mahmud Lodi is said to have accompanied Mahmud Ghaznavi in the campaign of Somnat. We hear of Malik Shahu Lodi, the deputy governor of Multan, in the reign of Muhammad bin Tughlaq , who gathered his Afghans followers and killed governor of Multan. Malik Bahram Lodi, grandfather of Bahlul Lodi, was serving governor of Multan with a contingent of his tribesmen in the reign of Feroz Shah Tughlaq. The Lodhis who seized Delhi throne in 1451 were not strange and new comers to India, they were active in India since times of Slave dynasty. They received Khan titles from their Turkish predecessors and continued to use it when they themselves became Sultans. The real Khan i.e Mughal Emperor Babur had to say that no one deserves Khan title batter than Afghan (it is said that six thousands soldiers in his army during panipat campaign were Afghans , notably of Zamand and Kheshgi tribes). Afghans remained important part of Mughal nobility and soldiery but Khan title was not exclusive to them, it was a Mughal title.
With the decline of Mughal empire in 18[SUP]th[/SUP] century, Pashtuns/Afghans settled in U.P, Malwa and Gujrat and seized territories there. Due to dominance of Pashtuns/Afghans in 18[SUP]th[/SUP] century Northern India, the prominent Khans roaming around were mostly Pashtuns and that’s why some how Khan became synonymous to Pathan among Indians.
Ghakkars, Janjuas, Awans, Balochs, muslim Rajputs etc have not borrowed Khan title from Pashtuns……..It was either bestowed on them by either old Turki dynasties of Delhi or by Mughals. Khizr Khan was a Sayyid but he was using Khan title. Khusrao Khan was a convert from Hinduism but he was given Khan name by Khiljis.
I doubt that Turk Sultans of Delhi would copy Khan title from Mongols. The younger brother of Balban was named ‘Kishlu Khan’. The most celebrated general of Khilji who destroyed Mongol armies, was zafar Khan.