The Bloody Tubs (or Blood Tubs) were a nineteenth-century gang of opportunistic street thugs in Baltimore, Maryland, who worked primarily for nativist Know Nothing politicians to commit election fraud.
Formed in the mid-1850s, the gang became known as the Bloody Tubs for their method of dunking political opponents in slaughterhouse tubs. Other sources claim it was due to the "bloody oaths" members took upon joining the gang. The gang's violent tactics included blocking voting booths and attacking opposing voters, discouraging many people from the polls altogether.
During the presidential election of 1860, the Blood Tubs reportedly planned to abduct, or possibly assassinate, then President-elect Abraham Lincoln when he visited Baltimore. They did however also at various times champion the Union cause. After the infamous Pratt Street Riot, the Blood Tubs could be seen sailing up and down the harbor flying U.S. flags.
The gang operated for more than a decade before their brutal acts caused so much public outrage that politicians were forced to withdraw their political support, and after 1870 the gang was eventually broken up by police "head smashers" or "strong arm squads" as were many other gangs of the era.