Empress Ci'an ("peaceful and motherly") was the second wife of the crown prince Xianfeng of the Ching dynasty.  When Xianfeng ascended the thrown, his first wife had died, and Ci'an was made empress.  She failed to produce a male heir to the throne.  Instead, a concubine, Yehenara, gave birth to the next crown prince.  When Emperor Xianfeng died, the prince was only five years old.  His mother received the honorary title of Empress, and became the infamous Ci'xi.  Unlike the iron-willed, ruthless Ci'xi, Ci'an was demure and peaceful.   Because she lived in the eastern part of the Forbidden City, Ci'an became known as the East Empress Dowager, and Ci'xi was the West Empress Dowager.  Together, they ruled as co-regents of the empire.