Rice was known in Roman times, but only medicinally, and was not grown in a regular or widespread way in the Mediterranean until the rise of Islam. Riziculture had its origins in India, Assam, Burma, Thailand, or China, and the plant slowly made its way west. Rice was cooked in the pilaf style in Muslim countries and in India, meaning it was light and fluffy with separate grains, while in northern Italy it was cooked in a manner similar to the way other grains were already cooked, namely, as a kind of porridge, aka risotto.
The fourteenth-century cookery manuscript known as the Libro per cuoco by an anonymous Venetian gives a recipe, rixo in bona manera–that is, a kind of porridge of rice cooked in almond milk with sugar. In Italy, a person who laughed easily was said to have eaten rice soup, a play on words: che aveva mangiato la minestra di riso (he had eaten laughter/rice soup).