The oldest documentation I have is from George Adam Kellenberger's Confirmation (Catholic) 1 Jun 1766...note the spelling variation.

"KILLENBERGER, George Adam, adult, admitted this day, 1 June 1766, to the sacraments (of penance and eucharist) born in Creutz-Steniach, in the Upper Palatinate, of a Catholic mother and a Calvinist father, instructed in Lutheranism by his step-father, but never professed this heresy, emigrated with his parents to Halifax seventeen years ago, came to Pennsylvania last year, and is now staying in Falkner's Swamp."