Yazid I was the son of Mu'awiya and was the second Caliph of the Ummayyad Dynasty. He became Caliph the day his that father died, 7 April 680. His father, Mu'awiya, designated Yazid as his successor, establishing hereditary succession as the norm for the Caliphate.
Yazid I was responsible for the death of <>Hussain
and his family at Karbala. He ruled for about four years. During his reign the Muslims conquered Khorasan and Khawirzam. He was also a poet and the first and the last lines in Arabic of the Ghazal with which Hafiz opened his magnificent Diwan were borrowed from Yazid.
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