Who was Mumtaz Mahal?

Mumtaz Mahal (also known as Aliya Begum, Arjumand Banu Begum, Taj Bibi, Mumtaz-ul Zamani) was the second and favorite wife of Mughal Emperor Shah Jahan for whom he created the most beautiful tomb, the Taj Mahal. She was the niece of Mughal Empress Nur Jahan (wife of Jahangir).