The image on the left is a photograph from the John W. Thomason collection. It is of soldiers marching with the American flag. John W. Thomason was stationed at the Legation in Beijing in the 1930s, so this is possibly the location of this picture.
The image on the right is a sketch by John W. Thomason. It seems to have been inspired by the picture on the left.
Even before leaving Huntsville, Texas, Thomason developed a habit of recording his surroundings in his drawing notebooks or on whatever scrap of paper he had nearby — which accounts for the large collection of diverse drawings held at Sam Houston State University.
See the original here: Marines marching, carrying flag
See the whole collection at : John W. Thomason drawings