I too enjoyed @JoNorvelleWalker's orgeat exploration.
But what brought me to this topic was the recipe for almond milk that is in "A Drizzle of Honey", which reconstructs the cuisine of the Jewish converso community of Inquisition Spain, as follows:
1C sliced almonds
2t sugar
2C chicken broth, water, or wine.
(Gitlitz D. and Davidson L., A Drizzle of Honey, 1999, p. 19.)
I nearly fell out! I had no idea almond milk could taste like anything other than sugar (which is what the stuff people buy in those boxes taste like to me, white-sugar-water).
Well, let's be honest. I had no idea that almond milk was an old-timey thing at all. I thought it was a newfangled pricey opportunity for plant-based living. You learn something new every day!