It turns out the precursor to the meringue was something called Snow Eggs, a popular dessert in Medieval and Renaissance Europe. In case you'd like to try it out, here's the handy 17th Century French recipe...
Snow eggsNow that's an easy one, right?
Boile some milk with a little flower water well allyed, then put it in more than half of one dosen of whites of eggs, and stir well all together, and sugar it. When you are ready to serve, set them on the fire again and glase them, that is, take the rest of your whites of eggs, beat them with a feather, and mix all well together; or else fry well the rest of your whites, and powre them over your other eggs. Pass over it lightly an oven lid, or the fire-shovell red hot, and serve them sured with sweet waters. You may instead of whites, put in it the yolks of your eggs proportionable, and the whites fried upon. The cream after the Mazarine way is make in the same manner, except you must put no whites of eggs on it."
---The French Cook, Francois Pierre, La Varenne, translated into English in 1653 by I.D.G., with an introdution by Philip and Mary Hyman [Southover Press:East Sussex] 2001 (p. 98-99)
Happy Lemon Meringue Pie Day to you!