OMG (+ a double !!) appears in a letter to Chuchill in 1917
OMG was first used in 1917 by British admiral John Arbuthnot Fisher in a letter to Winston Churchill –– an etymology that is recognized by the Oxford English Dictionary. SON! –– WITEF!!!
“I hear that a new order of Knighthood is on the tapis — O.M.G (Oh! My God!)— Shower it on the Admiralty!!”