linguistic:translation, information:extraction
Death toll

「賊臣不救，孤城圍逼，父陷子死，巢傾卵覆。」

— Excerpt from Yan Zhenqing 's Draft of a Requiem to My Nephew about the deaths of Yan Gaoqing (Magistrate of Changshan) and Yan Jiming

Censuses taken in the half-century before the rebellion show a gradual increase in population, with the last census undertaken before the rebellion, in 755, recording a population of 52,919,309 in 8,914,709 taxpaying households. However, a census taken in 764, the year following the end of the rebellion, recorded only 16,900,000 in 2,900,000 households. Later censuses count only households, but by 855 this figure had risen to only 4,955,151 households, little over half the number recorded in 755. The difference in the census figures amounts to 36 million people, two-thirds of the population of the empire, though scholars have attributed this to factors including a breakdown in taxation and census gathering.

The figure of 36 million was used in Steven Pinker 's book The Better Angels of Our Nature, where it is presented as proportionally the largest atrocity in history with the loss of a sixth of the world's population at that time, though Pinker stated that the figure was controversial. Matthew White, from whom Pinker had taken the figure of 36 million, later revised his figure down to 13 million (based on a different calculation from the census results) in his book The Great Big Book of Horrible Things. White's revised figure is repeated by cultural historians such as Johan Norberg.

Historians such as Charles Patrick Fitzgerald argue that claims of massive depopulation are incompatible with contemporary accounts of the war, which was fought intermittently over three or four provinces. They point out that the numbers recorded on the postwar registers reflect not only population loss, but also a breakdown of accuracy of the census system as well as the removal from the census figures of various classes of untaxed persons, such as those in religious orders, foreigners and merchants. In addition, several of the northern provinces, with approximately a quarter of the empire's population, were no longer subject to the imperial revenue system. For these reasons, census numbers for the post-rebellion Tang are considered unreliable.

The An Lushan rebellion was one of several wars in northern China along with the Uprising of the Five Barbarians, Huang Chao Rebellion, the wars of the Five Dynasties and Ten Kingdoms and Jin–Song Wars which caused a mass migration of Han Chinese from northern China to southern China called 衣冠南渡(yì guān nán dù). These mass migrations led to southern China's population growth, economic, agricultural and cultural development as it stayed peaceful unlike the north.