Two days before the riot, a fight broke out between a Black man and a white man outside a liquor store at the same intersection where Lorillard's factory stood. A police officer broke it up quickly, but the incident gave shape to grievances that had been building for years. In the Irish American neighborhoods of South Brooklyn, Copperhead newspapers had been warning that emancipation would send waves of freed Black workers north to steal jobs. The fact that Black workers at the tobacco factories already earned more than their white counterparts made the fear feel concrete. Rumors spread through the weekend — that Black workers had insulted white women, that they planned to move into the neighborhood, that they had offered to work for less than Irish wages. None of it needed to be true. By Monday morning, a crowd had gathered on the corner, and foreman William Egner could see what was coming.

At about eight o'clock on Monday morning, the mob surged toward the factory. They smashed the ground-floor windows and set a fire. The workers inside — primarily Black women and children — retreated to the second floor, where they barricaded themselves against the attackers. For roughly an hour, the barricade held. One worker, Charles Baker, was not so fortunate: the mob seized him and beat him severely. Police eventually arrived in sufficient numbers to disperse the crowd, douse the fire, and make arrests. But the damage extended beyond broken glass. T. Watson, who operated the neighboring factory, closed his Sedgwick Street location permanently. The Black workers who had commuted daily from across the East River would not be coming back.

Several rioters were arrested, including a man named Keenan whose lawyer requested a separate trial. The judge denied it. Over the following weeks, the case was delayed, rescheduled, and gradually drained of urgency. Newspaper coverage, which had initially called the riot 'one of the most atrocious of modern time,' tapered off by August 19. In late September, the judge dismissed the case entirely — at a hearing where neither the plaintiffs nor their lawyers bothered to appear. By then, several of the accused had enlisted in the Union Army, trading one form of organized violence for another. The dismissal was not unusual for the era. It was, in its quiet way, a statement about whose suffering mattered.

Historians now view the 1862 Brooklyn riot as the opening act of a longer, bloodier drama. In the weeks that followed, roving gangs of white men attacked Black residents across the area. From late 1862 through mid-1863, violent confrontations erupted along the Brooklyn docks as Irish strikers clashed with Black strikebreakers. Then came July 1863 and the New York City draft riots — five days of mayhem that killed over a hundred people, most of them Black, at the hands of working-class Irish mobs enraged by conscription and the exemptions money could buy. The patterns were identical: the same neighborhoods, the same economic anxieties weaponized into racial violence, the same targets. Sedgwick Street itself no longer exists, swallowed by the Columbia Street Waterfront District's postwar redevelopment. But the fault lines it exposed — between communities competing for survival at the bottom of an indifferent economy — proved far more durable than the street.