With his defeat in the third Anglo-Mysore war, Tipu was burning with revenge. He wanted to get back his territory and to achieve that objective he carried on negotiations with the French and Zaman Shah of Kabul. Tipu wanted his allies to expel the English. Lord Wellesley after making Subsidiary Alliance with the Nizam asked Tipu Sultan to accept the same but he refused. Mysore was attacked from two sides. The main army under General Harris supported by Nizam's subsidiary force under Arthur Wellesley attacked Mysore from the east while another army advanced from Bombay.
Tipu was at first defeated by the Bombay army and was later on defeated by the General Harris at Mallavalli. Tipu died fighting bravely. The members of his family were interned at Vellore. A boy of the earlier Mysore royal family was installed on the Gaddi of Mysore and a Subsidiary Alliance was imposed. Thus the fourth Mysore War destroyed the state of Mysore which was ruled by Haider Ali 33 years back.