Many believe this series of photos by the Strauss-Peyton studio were taken in the late 1910s but it seems they were actually taken in 1921, possibly following Charlie’s return from Europe. I think Charlie himself is to blame for the confusion because one of the photos from this shoot is in his autobiography with a caption that says “At the time of my marriage to Mildred Harris” (which took place in 1918).
The top photo appeared in a February 1922 issue of Photoplay as “His Latest Photograph” (The original photo was flipped in the wrong direction, so I flipped it back. This is a little pet peeve of mine.) The following copyright information is printed underneath the photo:
Another photo from the same session has a Strauss-Peyton stamp with the 1921 date (partially cut-off):
I also believe this commonly-seen photo is from the same 1921 session, Charlie is just wearing a different suit: