The man standing to the left of the open door is Charles Turner Cavileer. One of the two women to the right of the door is probably his wife, Isabell; the other woman and the tall man may be two of his five living children.
A history of the region published during the elder Cavileer’s lifetime called him “the father of Pembina” and “the oldest living settler of that locality,” adding that “he was a regular correspondent to the Smithsonian Institute.” It is likely, then, that the postmaster sent the photograph to us from his own post office. It was received in 1882, making it the first postal object added to the Smithsonian’s collection.
From Object of the Month, National Postal Museum, Smithsonian Institution