Hyder Ali Khan (; , ), Haidarali; 1721 – 7 December 1782) was the sultan and de facto ruler of the Kingdom of Mysore in southern India. Born Hyder Naik, he distinguished himself militarily, eventually drawing the attention of Mysore's rulers. Rising to the post of Dalavayi (commander-in-chief) to Krishnaraja Wodeyar II, he came to dominate the titular monarch and the Mysore government. He became the de facto ruler of Mysore as Sarvadhikari (Chief Minister) by 1761. He offered strong anti-colonial resistance against the military advances of the British East India Company during the First and Second Anglo–Mysore Wars, and he was the innovator of military use of the iron-cased Mysorean rockets. His sultanate ruled from 1768-1799, including the reign of his son Tipu Sultan when the sultanate was ceased post Anglo Mysore wars.