Analysis of information sources in references of the Wikipedia article "Milk substitute" in English language version.
The earliest document that mentions a plant-based milk - almond milk - dates back to a 1226 cookbook from present-day Iraq. [...] Soy milk [...] has roots in the Han Dynasty in China [...], in particular the early years of the Dynasty (202 BC to AD 9) when soybeans were ground and mixed with water to make soy milk [...].