Montage is a technique that is used in film editing to condense space and/or expand the idea of time. An example of montage, where a sequence of still images is used, is Chris Markers ‘La Jetee’ (1962).
With the still images, the idea of time is expanded. Another example of montage, but with film clips, is PJ Harvey’s music video for ‘Let England Shake’.
Her music, references a lot of political statements especially on the ‘Let England Shake’ album. The film clips in this video also have some nostalgia connected to them. A lot of the shots are of deserted places.
These are some more examples that are really nice.