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Before the British colonised the Indian subcontinent, Persian was the region's lingua franca and a widely used official language in what are now north India and Pakistan. The language was brought into the region by various Turkic, Persian and Afghan dynasties, in particular the Turko-Afghan Delhi Sultanate and the Mughal Dynasty. Persian held official status in the court and the administration within these empires and it heavily influenced many of the local languages, particularly Urdu and to some extent modern standard Hindi.
Evidence of Persian's historical influence there can be seen in the extent of its influence on the languages of the Indian subcontinent. Many of these areas have seen a certain influence by Persian not only in literature but also in the speech of the common man. Persian exerted a strong influence on Balochi (an Iranian language) and Urdu, and a relatively strong influence on Pashto (another Iranian language), Punjabi and Sindhi. Other languages like Hindi, Marathi, Gujarati, Kashmiri and Bengali also have a considerable amount of loan words from Persian.
Persian was one of the influential languages of the Ottoman Empire along with Ottoman Turkish and Arabic. It was initially used by the educated in northern portions of the Ottoman Empire before being displaced by Ottoman Turkish. Throughout the vast Ottoman bureaucracy Ottoman Turkish language was the official language, a version of Turkish, albeit with a vast mixture of both Arabic and Persian grammar and vocabulary. Educated Ottoman Turks spoke Arabic and Persian, as these were the main foreign languages in the pre-Tanzimat era, with the former being used for science and the latter for literary affairs.
The spread of the Persian language through Rumi shrines made it the dialect of the Sufism. The Ottomans promoted and supported the Persian language. The reborn evolution of the Persian etymology and its impact on the Turks’ literature and culture reached perfection in the Ottoman Royal Court and the Sufis’ Khanqahs. Sultan Bayezid II (1448- 1512), was in correspondence with the divines and the men of letters of Khorasan, including the poet Jami.
Constitution of the Republic of Dagestan: Chapter I, Article 11: "The state languages of the Republic of Dagestan are Russian and the languages of the peoples of Dagestan."
Jonson, Lena (1976) Tajikistan in the New Central Asia, I.B.Tauris, ISBN085771726X, p. 108: "According to official Uzbek statistics there are slightly over 1 million Tajiks in Uzbekistan or about 3% of the population. The unofficial figure is over 6 million Tajiks. They are concentrated in the Sukhandarya, Samarqand and Bukhara regions."