The Bloods gang was formed initially to compete against the influence of the Crips in Los Angeles. The origin of the Bloods and their rivalry with the Crips dates to the 1970s, where the Pirus street gang, originally a set, or faction, of the Crips, broke off during an internal gang war, and allied with other smaller gangs to found the gang that would eventually become known as the Bloods. At the time, Crips sets outnumbered Bloods sets by three to one. To assert their power despite this difference in numbers, Bloods sets became increasingly violent, especially against rival Crips members.
The Pirus are therefore considered to be the original founders of the Bloods. During the rise of crack cocaine, the gang's focus shifted to drug production. Bloods sets operate independently of each other, and are currently located in almost all States. Blood sets on the East Coast are often seen as affiliated with the United Blood Nation, a gang which originated in Rikers Island.
The United Blood Nation, simply called the Bloods, formed in 1993, within the New York City jail system on Rikers Island's GMDC (George Mochen Detention Center), sometimes called C 73. GMDC was used to segregate problem inmates from the rest of the detention center. Prior to this time period, the Latin Kings were the most prevalent and organized gang in the NYC jail system. The Latin Kings, with mostly Hispanic members, were targeting African American inmates with violence. These African American inmates, organized by some of the more violent and charismatic inmates, formed a protection group which they called the United Blood Nation. This United Blood Nation, which was actually a prison gang, was emulating the Bloods street gangs in Los Angeles, California. Several of the leaders of this recently created prison gang formed eight original Blood sets to recruit in their neighborhoods across New York City.
By 1996, thousands of members of the Blood street gang were establishing themselves as a formidable force among gangs and continued a steady drive for recruitment. At this time, the Bloods were more violent than other gangs but much less organized. Numerous slashings (razor blade or knife attacks) were reported during robberies and discovered to be initiations into the Bloods. This Blood in ritual became the trademark for the Bloods. Bloods recruited throughout the East Coast.