Quiet, well-meaning and earnest, I always think of them as the “Wasn’t it awful back then…” movies.

They are films that, set in the past, focus on an issue of social injustice – a persecuted gay man, a lesbian denied health benefits, a hounded interracial couple. The stories are often moving, even gripping.

Still, they tend to leave us not challenged, but secure. “Wasn’t it awful back then?” we think. And then we walk out.

“A United Kingdom” falls into this category. It’s a movie about a black African prince who falls in love with a white British insurance clerk – and finds that everyone, including both families, and both governments, are bitterly opposed to the match.

Their quick marriage only builds the fire higher, too. Returning to his nation, the British protectorate of Bechuanaland (now Botswana) Prince Seretse discovers his uncle’s disapproval has led to a constitutional crisis. And his new bride, Ruth, feels the sudden, strange shock of being judged by the color of her skin.

It’s a film that’s carried by its stars. The immensely calm and dignified David Oyelowo is both regal and human as Seretse – giving a rousing speech to his tribesman in one scene, softly weeping as he describes his love for Ruth in another. And Rosamund Pike gives Ruth both an English-rose beauty and gentle resilience.

Particularly good are the scenes of young love and early marriage – Seretse and Ruth jitterbugging in post-war London, or Ruth’s first wondering looks out an airplane window, at the gangling giraffes loping across the grassy plains of her new home. Those moments – particularly their first, hushed, honeymoon ones together – are the movie’s best.

Less involving, however, are endless scenes of the prince having to endure the snobbery and sneaky subterfuges of one British politician after another (played with icy scorn by Jack Davenport and good old Draco Malfoy, Tom Felton). Audiences unsure of the difference between a protectorate and a colony – or who Tony Benn was and why his entrance means something – will be at a loss, too.

Amma Asante – the Anglo-African filmmaker behind the more dramatic “Belle” – captures some wonderful images, like the African sunset that warms a day of particularly cold disappointments. Or small shifts in feeling, particularly the looks that pass between the women of Seretse’s tribe as they apprise the pretty interloper now in their midst.

But even for films about African royals and British bureaucrats, “A United Kingdom” feels a little too polite, too reserved. It never quite breaks from its own period; it never makes itself relevant to our own. While marked by romantic moments, and dramatic ones, it never pushes beyond them. It’s content to have us leave with a simple, superior “Wasn’t it awful back then?”

Ratings note: The film contains some racial slurs, brief violence and a scene of sensuality.

‘A United Kingdom’ (PG-13) Fox Searchlight (111 min.) Directed by Amma Asante. With David Oyelowo, Rosamund Pike. Now playing in New York. THREE STARS

Stephen Whitty may be reached at stephenjwhitty@gmail.com. Follow him on Twitter @stephenwhitty. Find him on Facebook.

Our editors found this article on this site using Google and regenerated it for our readers.