Volume I (1988), The Lands Below the Winds describes the pre-colonial region in terms of environment, physical well-being, material culture, social organisation and leisure activity.
Volume II (1993), Expansion and Crisis, defines the period through the rise and fall of external trade, urbanism, the political domination of maritime gunpowder states, and the transition to scriptural religions.
Reid avowedly follows the model of Fernand Braudel in asserting the coherence of a maritime region united by sea, despite differences in religion and culture, and in beginning with long-standing structures before proceeding to conjunctures, with the events (événements) seen as resulting surface phenomena.
Reid argues that the humid tropical environment suitable to rice agriculture and to maritime communication explain similarities in material culture and even folk beliefs despite the lack of unifying polity such as the Roman Empire in the Mediterranean.
His arguments are formulated from the perspective of the everyday life of the people, and include both the shared and unique characteristics of the nations of Southeast Asia created by large-scale maritime trade from 1450 to 1680, as well as the diversity of the natural environment and religion".