Chocolate Islands: Cocoa, Slavery, and Colonial Africa

In one sentence: Historian Catherine Higgs's account of the São Tomé and Príncipe cocoa slavery scandal is the backbone of Throughline's "The Bitter History of Chocolate" — she narrates almost the entire Cadbury–Nevinson confrontation herself, as the episode's principal historian-guest.

Overview

"Chocolate Islands: Cocoa, Slavery, and Colonial Africa" is commodity historian Catherine Higgs's account of the labor system on early-20th-century cocoa plantations in São Tomé and Príncipe. The book follows the chain of events that began in 1901, when Britain's Cadbury family discovered their cocoa supply was implicated in a slave-labor scandal: William Cadbury's inquiries to the Portuguese government, investigative journalist Henry Wood Nevinson's offer to investigate (and Cadbury's rejection of it), Cadbury's decision to send his own private investigator instead, and the libel trial that followed once the scandal went public. On the show, Higgs doesn't just narrate the sequence of events — she reconstructs William Cadbury's own internal conflict between business interest and Quaker religious conscience, and carries nearly the entire "Nevinson's Crusade" segment of the episode as its principal narrator.

Why It's Recommended

This book earns its place on sheer weight of evidence: Higgs carries almost the whole "Nevinson's Crusade" segment as narrator, moving from archival detail — a sales catalog listing laborers "along with the property and the machinery on a cocoa estate" — to psychological portraiture of how Cadbury's religious background and business calculus were entangled. Her storytelling is vivid: describing Cadbury's polite rejection of Nevinson, she says, "He rejects Nevinson. He's very polite to him, right? He's a Quaker. He's a pacifist." But what makes the book worth reading is her refusal to flatten Cadbury's motives into either hypocrisy or conscience — she insists both were true at once: "For Cadbury, it was a personal affront, this notion that his cocoa might have been produced by slave labor. He was also a businessman, and he needed a free source of cocoas." The libel trial she recounts lands as one of the episode's sharpest ironies: the jury ruled in Cadbury's favor, but awarded only symbolic damages — "One farthing, which is one quarter of one penny" — a verdict that quietly conceded Cadbury had indeed been hiding something. That refusal to let business history, religious history, and colonial labor history collapse into a simple morality tale is what makes an academic monograph play, in Higgs's telling, like a gripping investigative story.

Source

Catherine Higgs is the principal historian interviewed for Part 2, "Nevinson's Crusade," of Throughline's December 4, 2025 episode "The Bitter History of Chocolate," hosted by Ramtin Arablouei. The episode introduces her as "a professor of history at the University of British Columbia in Canada" who "wrote a book called... 'Chocolate Islands: Cocoa, Slavery, And Colonial Africa.'" Her narration carries the episode through Cadbury's discovery of the labor sale, his inquiries to the Portuguese government, his rejection of Nevinson in favor of his own secret investigator, and the libel suit Cadbury brought against The Standard — which he won, but with a one-farthing damages award.