Billion Dollar Brain (1967): Alexander Nevsky's Ice battle

Billion Dollar Brain is a 1967 Ken Russell film based on the novel Billion-Dollar Brain by Len Deighton. The film features Michael Caine as secret agent 'Harry Palmer', the anti-heroic protagonist of the cinematic versions of The IPCRESS File (1964) and Funeral in Berlin (1965).
The film's plot relies heavily upon the sophisticated 'brain' (computer) with which the FFF controls its Latvian anti-Soviet spy network. The film directly refers to the ice battle in Alexander Nevsky (1938), by Sergei Eisenstein.

Ice Battle of Lake Peipus
Several films have scenes strongly influenced by the Battle of Lake Peipus, including Doctor Zhivago (1965), Mulan (1998), and King Arthur (2004). However, the most striking homage appears during the culminating battle in Billion Dollar Brain.

Alexander Nevsky (1938)
This Soviet film portrays the struggle of Prince Alexander Nevsky and the citizens of Novgorod against invasion by the knights of the Crusading Order of the Teutonic Knights, culminating in the epic battle on the ice of Lake Chudskoe (Peipius). Prince Alexander Nevsky was later canonized by the Russian Orthodox Church and became a Russian national hero. This film was produced on the eve of World War II and alludes to the threat of Nazi Germany (note the swastikas on the Catholic bishop's mitre). Its showing was suppressed during the period of German-Soviet Non-Agression pact (9/39 to 6/41), but revived after the Nazi invasion. It was directed by Sergei Eisenstein with Nikolai Cherkasov in the title role.