Citizen Kane (1941) - and Gregg Toland's cinematography in particular - was a huge influence on Andrzej Wajda at the time. Like Toland, the first thing the film's cinematographer Jerzy Wójcik did was convince production designer Roman Mann to include ceilings in all the sets.
Zbigniew Cybulski came to be known as the Polish James Dean. A lot of this stemmed from Andrzej Wajda's direction of the actor, both having seen Dean on screen. Wajda wanted Cybulski to emulate Dean's air of diffidence and apparent "non-acting" for Cendres et diamant (1958).
After the film's release, sales of sunglasses shot up because Zbigniew Cybulski wore them consistently throughout the film.
One of Martin Scorsese's favorite movies. He showed it to Leonardo DiCaprio while making Les Infiltrés (2006), as main characters of these two movies have to deal with the same dilemmas.
Because of the film's nihilistic tone, the Polish authorities were not keen on it being exhibited outside of the country. Until a low-level official had a print shipped out to the Venice Film Festival where it played to great acclaim.