Cereal agriculture was established through much of mainland Southeast Asia around 4,000 years ago, but underwent important subsequent transformations. The first evi-dence for cereal-based agriculture in the southern parts of China and Taiwan dates to ca. 2500 BC or a few centuries earlier. While there are a few sites in mainland South-east Asia that might have involved cereal farming between 2500 and 2000 BC, includ-ing millet cultivation in Non Pa Wai, Thailand, most evidence is after 2000 BC. Current evidence suggests that lower yielding, and lower input, dry rice and millet cultivation are what first became established in mainland Southeast Asia. Wet rice, which is so common in the landscapes today, represents a later development, involving labour intensification and probably new varietal diversity in rice. The earliest evidence for this at present comes from ca. 100 BC at Ban Non Wat (Castillo et al. 2018b). Some of that new diversity included indica rice introduced from India (perhaps by the 3rd century AD), which dominate much of lowland irrigated rice in the plains of main-land Southeast Asia today. Additional diversity involved several pulse crops intro-duced from India, such as mungbean and pigeon pea, as well as cotton, all of which were established by Iron Age times (Castillo et al. 2016; D’Alpoim Guedes et al. 2020). Another strand of new diversity included glutinous rice, that spread as new japon-ica rice varieties from China, perhaps also in the last 2000 years. There is much less evidence for cereal agriculture in Island Southeast Asia and that is mostly within the past 3500 years – for example rice phytoliths of this age have recently been reported from Sulawesi (Deng et al. 2020a).