When I was a child, my family spent several summers in Amsterdam. My mother, sister and I toured the city, wandered along the canals, visited the great museums and sampled the local chocolates. My father, meanwhile, buried himself in Amsterdam’s social history library, studying the papers of the anarchists Emma Goldman and Alexander Berkman, known as Sasha. Sasha and Emma had been born in czarist Russia, immigrated to New York in the 1880s as teenagers, joined an anarchist group, and formed a lifelong friendship that remained immutable through protest rallies, bombing plots, prison time, love affairs, deportation, separation and war. My father, Paul Avrich, had been fascinated with them for years.

My father, who died in in 2006, was a professor of Russian history, a scholar drawn particularly to the radical underpinnings of that vast, doleful country. While he was researching the threads of political and social unrest, he was led to investigate anarchism and its adherents, men and women from around the world who espoused a Utopian society without government and fought tirelessly for their improbable goal.

When my father began to interview anarchists who had been active at the height of the movement in the early 20th century, he was smitten by their vivacity and stubborn idealism, intrigued by the stark contradictions of fanaticism and cerebral enlightenment. He traveled to meet them, listened to their stories, perused their precious letters and photographs, disarmed them with his palpable enthusiasm and curiosity. He chronicled their political influence, heroism, crimes and misdeeds, and became known as the leading scholar of the anarchist movement. He wrote about Russian uprisings, ruthless bomb makers, the doomed Sacco and Vanzetti, the tragic Haymarket incident....