Untamed (1955)

Tyrone Power plays a South African cavalry commander trying to bring peace to his country during the Boer War. Susan Hayward plays an Irishwoman who's immigrated to escape the Irish potato famine, but whose husband was killed during a native insurgency. When Power has an illicit affair with Hayward, a Dutch farmer (Richard Egan) claims that the woman is his property and then becomes a renegade who attempts to pilfer the South African diamond mines. Power pursues Egan to defeat the farmer at the mines and then claim Hayward for himself.