I have a soft spot for British Films so a lot below are British... All based on real events, with some the "events have been stretched for dramatic effect" All worth a look, some better than others.
Saving Private Ryan.
Flags of our Fathers
Letters from Iwo Jima
Dunkirk
D Day.
Carve her Name with Pride.
Sink the Bismarck.
Battle of the River Plate.
Colditz
Battle of Britain.
First of the Few.
Target for tonight
In which we serve (Based loosely on the story of HMS Kelly)
Target for Today. Semi documentary, famous for its unparalleled sequences of the brutal battles waged at 30,000 feet.
Scott of the Antarctic
Whiskey Galore (based on the shipwreck of HMS Politician)
David Lean’s Film Madeleine
Odette ( story of female agent of SOE)
The Magic Box ( Gave a biographic account of William Friese-Greene who first designed and patented a working cinematic camera. The accuracy of this claim is subject to some controversy, but evidence now tends to support the claim)
Moulin Rouge (1952)
Breaking the Sound Barrier. (The story is not a comprehensive (nor wholly accurate) account of the attempts to break the sound barrier, giving only a fictional and parochially British view, albeit considered an entertaining and visually stunning depiction, especially at the time of release.)
The Cruel Sea, based on the book by Nicholas Monsarrat It is a strikingly accurate portrayal of the war between the Royal Navy and Germany's U boats from the viewpoint of the British naval officers and seamen who served in escort vessels during WWII
The One That Got Away, which chronicled the true exploits of Oberleutenent Franz von Werra a German flyer shot down over England.
Yangtse Incident: The Story of HMS Amethyst
I Was Monty's Double
Becket
Zulu
A Man for all Seasons.
The Lion in Winter
Mayerling.
Anne of a Thousand Days.
Cromwell.
The Music Lovers
10 Rillington Place.
Nicholas and Alexandra
Adolf Hitler: My Part in His Downfall is a film adaptation of Spike Milligan's autobiography
Young Winston
Mahler (about Gustav Mahler)
A Bridge too Far
The Elephant Man
McVicar
Chariots of Fire.
The Bounty
The Killing Fields.
Lady Jane
84 Charing Cross Road.
Cry Freedom
Hope and Glory
Buster
My Left Foot.
Scandal
The Krays
Memphis Belle
In the name of the Father
Backbeat
The Madness of King George.
Carrington
Stonewall
Mrs Brown
Elizabeth
Tea with Mussolini
Calendar Girls
Enigma
Iris
Touching the Void.
The Life and Death of Peter Sellers
Mrs Henderson Presents.
Becoming Jane.
Elizabeth the Golden Age
The Duchess
The Queen