People's Liberation Army troops entered Beijing on 31 January 1949, after the Nationalist troops had left the city. The location shown on this image is near Qianmen, one of the gates of TIan'anmen Square.
The original painting is from 1959 and in the collection of the Museum of the Chinese Revolution.
"Beiping" (北平) is a former name of Beijing (北京), used until 1949.