Again in February 1850, in command of militia, he went with Sir Charles Napier to the forcing of the Kohat pass and guided him through that defile. In July 1850 he became political agent in Méwar, one of the Rajputana states, where he remained until 13 March 1857, when he succeeded his brother Henry Lawrence as resident or chief agent for the governor-general in the Rajputana states, and in April took up his residence in Abu. On the breaking out of the Indian rebellion of 1857 he was named brigadier-general of all the forces in Rajputana, and on the death of Colonel Dixon on 12 June 1857, he took chief military command. By his vigorous and decided action the arsenal of Ajmer was retained; a proclamation confirmed the native princes in their loyalty, and the Rajputana states were prevented from joining the revolt. Such outbreaks as did take place were successfully quelled, first by himself, and afterwards by Major-General Roberts.