The Battle of Red Cliffs, otherwise known as the Battle of Chibi, was a decisive naval battle in the winter of AD 208–9 at the end of the Han dynasty, about twelve years prior to the beginning of the Three Kingdoms period in Chinese history.[2] The battle was fought between the allied forces of the southern warlords Sun Quan, Liu Bei and Liu Qi against the numerically superior forces of the northern warlord Cao Cao. Liu Bei and Sun Quan frustrated Cao Cao's effort to conquer the land south of the Yangtze River and reunite the territory of the Eastern Han dynasty.The allied victory at Red Cliffs ensured the survival of Liu Bei and Sun Quan, gave them control of the Yangtze and provided a line of defence that was the basis for the later creation of the two southern states of Shu Han and Eastern Wu.(de Crespigny 1990:273) The battle has been called the largest naval battle in history in terms of numbers involved.[3] Descriptions of the battle differ widely and the site of the battle is fiercely debated (de Crespigny 1990:256 78n). Although its location remains uncertain, the majority of academic conjectures place it on the south bank of the Yangtze River, southwest of present-day Wuhan and northeast of Baqiu (present-day Yueyang, Hunan).