The Battle of the River Plate (1956), written, produced and directed by Michael Powell and Emeric Pressburger.
Aka Pursuit of the Graf Spee.
It's one of Powell & Pressburger's most successful films, but I doubt if fans will rank it among their best. Still it's of interest because, although a patriotic history, the Germans are not demonized, which must have been hard then.
The narrative loosens up a bit post-battle when we have the military and diplomatic maneuvering. This section seems more Powell-like than the rest.
Familiar faces include Anthony Quayle, Bernard Lee, Christopher Lee and Patrick Macnee (later "John Steed").
Brian Easdale gives a rousing maritime score.