Urdu is mutually intelligible with Standard Hindi spoken in India. Both languages share the same Indo-Aryan base and are so similar in basic structure, grammar and to a large extent, vocabulary and phonology, that they appear to be one language.
From the 13th century until the end of the 18th century the commonly known language from Delhi to the Awadh region was Hindvi. The language was also known by various other names such as Hindavi and Dehlavi. Hindvi later developed into Hindustani—which further diverged as Hindi and Urdu in the 18th century. The first Hindustani book "Woh Majlis" was written in 1728.
Standard Hindvi was first developed by the Turkish speakers of Khari Boli who migrated from Delhi to the Awadh region—most notably Amir Khusrau and mixed the roughness of the Khari Boli with the relative softness of Awadhi to form a new language which they called Hindvi.
Khariboli, also known as Dehlavi, Kauravi, and Vernacular Hindustani, is a Western Hindi dialect spoken mainly in the rural surroundings of Delhi, the areas of Western Uttar Pradesh and the southern areas of Uttarakhand in India.
The earliest examples of Khariboli can be seen in the compositions of Amir Khusro (1253-1355). Before the rise of Khari Boli, the literary dialects of Hindvi were the ones adopted by the Bhakti saints: Braj Bhasha (Krishna devotees), Awadhi (adopted by the Rama devotees) and Maithili (Vaishnavites of Bihar).
Based on the Khariboli dialect of Delhi, Hindvi developed under the influence of Persian, Arabic, and Turkic languages over the course of almost 900 years. It originated in the region of Uttar Pradesh in the Indian subcontinent during the Delhi Sultanate (1206–1527) and continued to develop under the Mughal Empire (1526–1858).
The area around Delhi has long been the center of power in northern India, and naturally, the Khariboli dialect came to be regarded as urbane and of a higher standard than the other dialects of Hindvi. This view gradually gained ground over the 19th century; before that period, other dialects such as Awadhi, Braj Bhasha, and Sadhukaddi were the dialects preferred by littérateurs.
In 1800, the British East India Company established a college of higher education in Calcutta named the Fort William College. John Borthwick Gilchrist, a president of that college, encouraged his professors to write in their native tongue; some of the works thus produced were in the literary form of the Khariboli-based Modern Standard Hindustani.
With the advent of the British Raj, Persian was no longer the language of administration, but Hindustani, still written in the Persian script, continued to be used by both Hindus and Muslims.
The British administrators of India and the Christian missionaries played an important role in the creation and promotion of the Khariboli-based Modern Standard Hindustani.
With the government patronage and the literary popularity, the Khariboli-based Modern Standard Hindustani flourished, even as the use of previously more literary tongues such as Awadhi, Braj, and Maithili declined in the literary vehicles.
The literary works in Khariboli-based Modern Standard Hindustani gained momentum from the second half of the 19th century onwards. Gradually, in the subsequent years, Khariboli-based Modern Standard Hindustani became the basis for the standard Hindustani, which began to be taught in the schools and used in the government functions.
Hindustani was promoted in British India by British policies to counter the previous emphasis on Persian. This triggered a Hindu backlash in northwestern India, which argued that the language should be written in the native Devanagari script.
Thus a new literary register, called "Hindi", replaced traditional Hindustani as the official language of Bihar in 1881, establishing a sectarian divide of "Urdu" for Muslims and "Hindi" for Hindus.
The Urdu language received recognition and patronage under the British Raj when the British replaced the Persian with the Urdu language in local offices of Punjab in 1877 and in North Indian Jammu and Kashmir state in 1889.
The Modern Standard Urdu, the heavily Persianalized version of Khariboli-based Modern Standard Hindustani, had replaced Persian as the literary language of North India by the early 20th century. However, the association of Urdu with the Muslims prompted the Hindus to develop their own Sanskritized version of the dialect, leading to the formation of the Modern Standard Hindi.
The Modern Standard Urdu is 21st most spoken languages of the world. There are between 60 and 70 million native speakers of Urdu: there were 52 million in India per the 2001 census, some 6% of the population; approximately 10 million in Pakistan or 7.57% per the 1998 census; and several hundred thousand in the United Kingdom, Saudi Arabia, the United States, and Bangladesh (where it is called "Bihari").
Urdu is one of the officially recognized languages in India and has official language status in the Indian states of Uttar Pradesh, Bihar, Telangana, Jammu and Kashmir and the national capital, New Delhi.
In Pakistan, Urdu is mostly learned as a second or a third language. Nearly 93% of Pakistan's population has a native language other than Urdu. Despite this, Urdu was chosen as a national language of Pakistan by the first Prime Minister of Pakistan, Liaquat Ali Khan.