Norman Gilbreath published the Gilbreath Principle in the context of the trick “Magnetic Colors” in The Linking Ring, Vol. 38 No. 5, July 1958, p. 60.
There were several “proto-Gilbreath” (as Max Maven calls them) tricks that predate Gilbreath's own work, where the principle was there, but just not fully understood at the time. This includes work by Charles Jordan (see Four Full Hands of Down to the Minute Magical Effects, 1921, “The Psychic Prediction”, p. 34 of the 1947 reprint) or J. Russell Duck (see The Cardiste, No. 1, Feb. 1957, p. 12).
While the principle is commonly thought of as being riffle-shuffle based, its use is more versatile. For example, Felix Greenfield's marketed trick, “Colorific,” c. 1959, used the concept of using a stack to force a group of a known make-up, by inviting someone to take cards in any combination from the top and bottom of a packet. See Karl Fulves's The Fine Print, No. 10, p. 309, for a reprint of this trick. Nick Trost applied this principle to a selection from the tops of two packets in his “'Seven Card Draw' Prediction,” from New Tops, Vol. 9 No. 11, Nov. 1969, p. 22. This is also reprinted by Fulves, ibid., p. 313.