Mary Pickford, Charlie Chaplin, and Douglas Fairbanks woulda been the big names at the time; D.W. Griffith's Intolerance came out about three weeks prior and was cleaning up pretty well at the 1916 equivalent of the box office
That was pretty much the year movies became that big; Griffith's Birth of a Nation, released the previous year, more or less revolutionized the filmmaking process and near-singlehandedly codified long-form cinema as we know it today. Of course it also made the KKK the good guys, so, you know, some aspects coulda been better.
Great question! Wikipedia has the answer. Charlie Chaplin was in his prime. D.W. Griffith put out "Intolerance", which I've read about but never seen. Several Cecil B. DeMille movies. And, of course, Everett True had one of his shorts.