In the Second Sikh War, in 1849, Birch was appointed to the temporary command of a brigade after the Battle of Chillianwallah. He distinguished himself at the Battle of Gujrat, and was made a Companion of the Order of the Bath in 1849, and continued to serve as brigadier-general in Sir Colin Campbell's campaign in the Kohat Pass in 1850. He then reverted to his appointment at headquarters, and in 1852 received the still more important post of secretary to the Company government in the military department. While in this office, he was promoted to colonel in 1854, major-general in 1858, and still held the secretaryship when the Indian Mutiny broke out in 1857.