Autumn in the Heavenly Kingdom by Stephen Platt is a great look at China's Taiping war in the mid-1800s and the country's fraught relations with western powers (Second Opium War).
How about something outside of the usual Western view of the world? In China, there was a civil war caused by Christian rebels that killed as many as 20 million people between 1850-1864.
Autumn in the Heavenly Kingdom: China, the West, and the Epic Story of the Taiping Civil War