A United Kingdom

It's remarkable that the story of Seretse Khama, the king of Bechuanaland, isn't more popularly known, though Amma Asante's film may change all that. The movie opens in a smoggy, gloomy London in 1947, where Seretse (David Oyelowo) is completing his studies in law prior to returning to rule his homeland. Momentous change is in the air in the post-war world, as Europe struggles to rebuild and Indian independence signals sundown on the British Empire. 

Seretse encounters filing clerk Ruth Williams (Rosamund Pike) at a London Missionary Society dance, where their eyes meet across a crowded room. With remarkably little preamble or soul-searching from the protagonists, not only romance ensues, but nuptials.

Getting 'A United Kingdom' made has been a labour of love for David Oyelowo

A mixed-race marriage in 1940s London must have been controversial enough, but in the southern half of Africa, as South Africa introduced its apartheid laws, it was dynamite. It's hard to believe that Seretse didn't anticipate the storm that was about to break over the couple's heads, both from the British colonial authorities and also from his outraged uncle (and acting regent in Bechuanaland) Tshekedi (Vusi Kunene). As Asante and screenwriter Guy Hibbert show us here, huge political pressure was heaped on the couple from South Africa, the British government and Seretse's own people, and it was only after years of exile that he was able to return to Bechuanaland to become Prime Minister of what is now Botswana.

Getting A United Kingdom made has been a labour of love for Oyelowo, and the story's David-and-Goliath aspect and mix of power, politics and race give it blockbuster potential. It's a shame, then, that it suffers from some painfully simplistic characterisation. Seretse and Ruth's relationship is presented as an idyllic romance amidst Out of Africa-style scenes under sunny southern skies, but while we see Ruth looking bored doing her fusty Dickensian office job, we never fully understand what drove her to give everything up for a new life in a very primitive Third World country. The fact that the couple have to spend large chunks of time living on separate continents doesn't help to bind the narrative together.

Meanwhile, it's open season on the British establishment. Okay, everybody hates the snobby racist Brits and their imperial pretensions, but Jack Davenport's sneering, patronising Sir Alistair Canning, HMG's man in southern Africa, makes Flashman from Tom Brown's Schooldays look like Gandhi, while the English colonial wives resemble Penelope Keith's Margot Leadbetter on steroids and pink gin (intriguingly, Oyelowo's wife Jessica plays Canning's snooty wife, Lady Lily). Even Ruth Williams's drab, disapproving father (Nicholas Lyndhurst) resembles a closet Hitler impersonator.

In a different film altogether, more could have been made out of the political brouhaha the Seretse case aroused back in London, where we see a posse of crusading MPs (including Tony Benn) campaigning on Seretse's behalf, while Labour Prime Minister Clement Attlee (Anton Lesser) succumbed to South African threats to cut off gold and uranium supplies. Meanwhile Winston Churchill played a cynical game of backing Seretse while in opposition, then dropping him when he got re-elected.

All the while, the handsome Seretse is the acme of politeness, wisdom and decency, and speaks much better English than the oafish colonials. Obviously the real Seretse must have been an extraordinary man, and his gambit of renouncing his royal status in favour of democratic elections was masterly, but even he must have had the occasional off day. Nonetheless, it's an amazing real-life tale, and the brutal realpolitik underpinning it still carries powerful resonance today.

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