It is ironic that one of the great challenges of political activism across borders is taking the obscure complexities of a globalised economy and making them legible and local.

Even today, with so much direct visual evidence of exploitation and violence at our fingertips, apologists are quick to tell us that any given situation of which we don’t have first-hand knowledge is simply too complex for us to really grasp. It can take remarkable dedication and a talent at communication to blow away the smoke and explain the system at play, a process which often reveals, at the core, nothing more complex than old-fashioned rape and pillage. Behind complex politics can lie simple moral truths.

In his new biography, Broken Archangel: The Tempestuous Lives of Roger Casement, Roland Philipps uncovers one such remarkable talent, the Irish diplomat Roger Casement. Beneath Casement’s many often- conflicting identities — colonial administrator, British consul, humanitarian reformer, knight of the realm, anti-colonialist rebel, gun-runner, and revolutionary — was a deep moral vision which revealed the simple violence of colonialism, firstly to himself, and then to a wider public. Without it, his life could have gone any number of ways.

Born the son of a Protestant British army officer in Dublin in 1864, it seemed inevitable that Casement would live a life in service of the Empire. Despite losing both parents before the age of 14, that fate looked inescapable. As a young man he took a job working for the International African Association, an organisation established by King Leopold II of Belgium as a humanitarian organisation. In reality, its function was to establish the Congo Free State, a private state, as the king’s personal property.

The horrors of the colonisation of the Congo Free State are hard to fathom. Rich in rubber and ivory, the Congo became a virtual slave state whose people were forced to harvest its natural wealth for the king under a regime of inhuman barbarity. Production quotas were impossibly high, enforced by a police force schooled in mutilation and murder. Local resistance was easily outgunned, and, with upwards of 50 percent of the population being killed in rubber-producing areas, some estimate as many as 10 million people may have died under Leopold’s rule.

Witnessing this genocide unfold, Casement joined first a Baptist mission, then the British Colonial Service, where he authored the Casement Report, an extensive investigation into the atrocities. The public outcry was unprecedented, leading to growing support for his associates like the campaigner E. D. Morel and the Congo Reform Association. Casement followed up the report with another, which investigated human rights abuses against Putumayo Indians in Peru. While some of Casement’s language might seem a little off to contemporary ears, at the core what marked Casement out as different from his government contemporaries was his understanding of colonial subjects as human beings of equal worth and intelligence, and hence important witnesses to the violence they were enduring. Unlike his contemporaries, Casement put the voices of those suffering from colonial violence at the centre of his work and allowed them to speak directly to the world through him. It was these compelling voices that were heard back in the heart of the Empire.

Casement was lauded by the British state and knighted. Yet he had joined the economic and political dots; and seeing how his homeland had been the ground zero of Britain’s own colonial project, he slowly turned his romantic, cultural Irish nationalism into a militant, revolutionary campaign. Joining Sinn Féin, he travelled extensively in the United States to fundraise for nationalist causes. At the outbreak of the First World War, he saw his chance. Smuggling himself into Germany, he negotiated with the German government for weapons and training to aid an Irish insurrection against British rule. Welcoming any distraction to the British war effort, the Germans provided Casement with a cache of arms to smuggle into Ireland. Disaster struck when the British intercepted the shipment, and Casement himself was caught after reaching Ireland by U-boat. Tried by the British in London as a traitor, he was executed at Pentonville Prison four months after the failed Easter Uprising.

Casement might well have been lauded as a martyr for Ireland immediately after his death, had it not been for the exposure of his homosexuality during his trial. Detailed erotic diaries recounting his frequent sexual encounters with men across the world were revealed during his imprisonment. His supporters wanted to claim this was evidence of his mental and physical instability — he had battled recurrent sickness since his time in the Congo — and urged for a defence of madness, something he courageously rejected. The British claimed he was ‘addicted to the grossest sodomitical practices’.

Casement’s sexuality led to an uneasy relationship with his memory. Some have unconvincingly rejected the diaries as hoaxes in an attempt to redeem his legacy, while others have looked for psychosexual drivers for his ‘treachery’. Philipps, admirably, avoids both, finding more evidence for his passionate rejection of brutality and desire for home in his difficult childhood. Instead, he situates Casement’s desire for men within his whole personality: as a man of deep, sensitive courage trying to uncover the most human traces of good in a world of cruelty and exploitation.