During his early years as a scholar and academic, de Crespigny benefited from the guidance of Geoffrey Elton and sinologists such as Hans Bielenstein, Otto van der Sprenkel, Fang Chao-ying, Liu Ts'un-yan,[8] and Göran Malmqvist, and he developed an interest in the late Han dynasty through the historical novel Romance of the Three Kingdoms.
His doctoral dissertation of 1968 on the development of the Chinese empire in the south and the origins of the Three Kingdoms state of Eastern Wu has provided the basis for much of his later work.
The approach owes a great deal to the narrative tradition of the historical novel Romance of the Three Kingdoms but Generals of the South also discusses the population and development of southern China from the second century AD.
In dealing with the military defence of the south via the boundary of the Yangtze River, it presents the best discussion of the Battle of Red Cliffs and early Chinese riverine warfare available in English.
[citation needed] The work also provides an important prelude to further research into the political and cultural divisions of the Northern and Southern dynasties.
[10] He was brought on as a consultant for the Creative Assembly strategy video game Total War: Three Kingdoms (released 2019).