Yom-e Bab ul-Islam (Urdu: یوم باب الاسلام) is observed on 10th Ramadan to commemorate the establishment of Muslim rule by Muhammad bin Qasim in modern Pakistan in 711 AD. Muhammad bin Qasim Al-Thaqafi was an Umayyad general who, at the age of 17, began the conquest of the Balochistan, Sindh and Punjab, Kashmir regions along the Indus River (now a part of Pakistan) for the Umayyad Caliphate. He was born and raised in the city of Taif (in modern-day Saudi Arabia). Qasim's conquest of Balochistan, Sindh and Punjab laid the foundations of Islamic rule in the South Asia.
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Yom-e Bab ul-Islam Wikipedia(Text) CC BY-SA