I'm a bit of a cineaste, albeit one that doesn't get to see many films these days. As a child, I grew up with depictions of World War Two on television every public holiday: Easters and Christmases were filled with Where Eagles Dare, The Battle of the Bulge, A Bridge Too Far and the like. While I still have a bit of a soft spot for these, their depictions of WWII are often close to revisionist in the way that they play fast and loose with the facts. I've come to appreciate the very specific genre of British-made films, and the way that they portray the British experience in WWII. Moreover, I have a specific interest in those films that were made during WWII, when an Allied victory was by no means a certainty. These films are propaganda - I can't deny that - but they speak volumes about contemporary British society through the way that they try to engage with and exhort the British viewing public.
There are number of films about the British experience that have failed to make it onto this list for one reason or another. To my undying shame, I've failed to watch all of The Life and Death of Colonel Blimp, and I haven't seen any of A Canterbury Tale. Rest assured, both are on my to-see list.
Mrs. Miniver was excluded from the list as a US production, while the marvellous A Matter of Life and Death was released in 1946, one year too late (The Way to the Stars fails by an even narrower margin, being released a scant month after VE Day).
5. Night Train to Munich (1940)
This is a bit of a cheat; it isn't strictly speaking a film about the war in Europe (or the war at home, for that matter), but a thriller set against the backdrop of the German invasion of Prague. A Czech scientist and his daughter flee the Nazis, with Rex Harrison playing the hero, Paul Henreid playing the villain (though he makes a better hero than villain, as in Casablanca (1942) for example), and Basil Radford and Naunton Wayne reprising their roles as the cricket-mad English duffers Charters and Caldicott (previously seen in Hitchcock's The Lady Vanishes).
I have to admit, Charters and Caldicott are my main reasons for choosing this film. They appeared in two other wartime films: Crook's Tour (1941) and Millions Like Us (1943). I've not seen the latter, unfortunately; by all accounts, it sounds a little like The Gentle Sex (1943) without the (unintentionally) patronising voiceover.
4. The First of the Few (1942)
This is a film with local appeal for me. The First of the Few follows the development of the Spitfire by R.J Mitchell; I live on the northern edge of Southampton, a brisk ten minute walk from the airport from which the Spitfire took its maiden flight. Few also has the distinction of being Leslie Howard's last film; he died in 1943 on the way back from Lisbon when his plane was shot down over the Bay of Biscay
For a film about the Spitfire, it has remarkably few flying scenes (unsurprising, given that the Spitfires were in greater demand in the theatre of war than in the studio). If I wanted something more spectacular in that line, I'd choose the 1969 film Battle of Britain, but not for this top five.
3. The Way Ahead (1944)
A fairly standard training tale, directed by Carol Reed and script-written by Peter Ustinov. David Niven as the commander of a unit of new recruits, with William Hartnell as the sergeant trying to turn a mismatched group of civvies into soldiers. Excellent realistic cinematography, with pleasingly unstereotyped performances from the ensemble cast.
2. In Which We Serve (1942)
Noel Coward's contribution to wartime morale, supposedly based on the exploits of Lord Louis Mountbatten. Notable for the screen debut of a very young Dickie Attenborough, and a nicely measured role by John Mills (I almost put 1943's We Dive at Dawn in this slot, on the strength of Mills' role there, but Attenborough's presence meant this won out).
1. Went the Day Well? (1942)
Went the Day Well? is a film by the redoubtable Ealing Studio. Based on a story by Graham Greene, it follows the inhabitants of the sleepy village of Bramley End when they are invaded by German paratroopers disguised as British soldiers. It's a genuinely shocking film to those raised on the easy certainties of WWII films of the 1960s and later, and a very effective piece of propaganda; characters are killed without warning, and there are a couple of false starts before the situation is resolved.
In the running, but not placing, were the Powell and Pressburger collaborations One of our Aircraft is Missing (1942) and The Silver Fleet (1943) - embarrassingly, no Powell and Pressburger films have made my list, though A Matter of Life and Death only missed out due to its release date.