Turks in India

                                   Turks in India

Mughal contingent, Jama Masjid, Delhi

Along with Arabs, Turks are the only Muslim ethnicity that is global, you will find them in Central Asia as well as in the South Eastern Europe, You can also find them in Middle-East as well as in North Africa.
That is due to the fact that Turks and Turkic people ruled these areas and served in the armies of local rulers as well, because of they were good able and skillful soldiers. They had ruled in almost every part of Asia except far east and south east.

Seljuk Cavalry 

Along with that the Turks had also ruled over the subcontinent(India, Pakistan, Bangladesh and Afghanistan) from the Ghaznavid Empire to the late Mughal Empire. Out of approximately 750 years of the Muslim rule in subcontinent.Turks ruled about 650-670 years. Their rule was mainly on northern subcontinent in the west from Kabul and Ghazni in modern day Afghanistan to East in Bangladesh and Deccan as far as the southern/central regions are considered. Along with the rulers their armies of thousands of Turks settled in northern subcontinent with their families specially where the rulers made their capital or in the nearby regions of it. Particularly in Delhi as it was the centre of the power and capital of the medieval rulers. They settled in Delhi and its neighbouring areas of Moradabad, Sambhal, Rampur, Badaun, Amroha and other areas particularly of western Uttar Pradesh(U.P.) and some parts of Punjab near by Lahore. Western UP was famous with the name of Rohilkhand in late medieval and British period due to the Pashtun settlement in the area during Mughal and British rule. These areas along with Delhi were the centres of the power of these Turkic rulers from where they managed the affairs of the subcontinent.
Apart from that during the reign of Mamluk/Slave dynasty from 1206 to 1290 AD. Hordes of Turks came from Central Asia to settle in the Delhi-Western UP region due to the Mongol attacks in central asia during that era.

Oguz Turks

These tribes were the Oguz turks, Kipchaks, Cumans, Uyghurs and other Turkic tribes from Khorasan and Iran and various other clans of them and Non-Tukic people as well. This continued in Khilji sultanate as well as in the Tughluq sultanate.
During the reign of Mamluk Sultan Balban, he broke the Amir Chalgani which was a group of 40 nobles in the court which was formed by his predecessor Altamash. They fled and settled in western UP.
Later during the invasion of the Turko-Mongol ruler Timur Leng,  the Karluk Turks settled in the hazara regions of modern day Khyber Pakhtunkhwa (Pakistan) and Punjab. In the time of Timur's descendant Mughal emperor Babur various other Turkic and Turco-Mongol tribes came and settled in the northern regions these were in particular the Barlas, Qazilbash, Uzbeks, and various Central Asian Turkomen tribes and other Non-Turks such as Persians, Tajiks, Afghans.

Mughal Court

Further during the reign of Mughal empire in particular, it attracted lots of Migrants from all over asia and middle east due to its prosperity and opportunities. And migrants were not just Turks but Persians, Arabs, Kurds, Afghans also came in big numbers and settled in the Northern and Deccan regions of subcontinent. Later in the Mughal reign the Turks started to call themselves as Mughals taking it as an honorary title specially those who served under the empire.
Today most of the modern populations of Turks are ignorant of their roots. But surnames such as Baig/Beg, Mirza, Mughal, Turk, Turkei, Khan tells alot about their history.
This fusion of the migrants and along with local muslim converts and non muslims developed the culture and tradition of "Ganga-Jamni Tehzib". This diversity made a culture which was famous for its cuisines and  Urdu language which was the merger of Arabic, Persian, Turkish with Hindustani, Sanskrit. And this melting pot of cultures over the years gave rise to the Urdu speaking Indian muslim population of modern times in Delhi, Up, Bihar, Hyderabad and other states. Most well known example is of Mirza Ghalib aka (Mirza Asadullah Khan Baig) who himself was a Turk and widely known as the pioneer and most influential writer of Urdu literature. Some say he is the Shakespeare of Urdu language. During partition many of the Turks-Mughals  migrated to Pakistan. Nevertheless there is still a big chunk of them living in Delhi and western UP thriving to make their lives better & prosperous.

Further Read:
https://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjb7c7_m4HSAhWBpI8KHcz0A6AQFggZMAA&url=http%3A%2F%2Ftimesofindia.indiatimes.com%2Fcity%2Fbareilly%2FIstanbul-opens-its-eyes-to-Rohilkhands-11-lakh-Turks-%2Farticleshow%2F49263392.cms&usg=AFQjCNEe8gjPRXIs6LlUfdMoccJumdh9qA&sig2=gc_EwCQurMgTv8nniRS3Aw&bvm=bv.146496531,d.c2I