The Alex Boncayao Brigade (ABB) was initially created as a faction of a pre-existing terrorist organization, the New People's Army. The New People's Army (NPA) was formed in 1969 as the armed wing of a Filipino communist organization. Since its inception, the NPA remained committed to the idea that a worker-peasant alliance manifested through a jungle-based guerilla movement was the most likely path to revolutionary victory. In the early 1980s, a faction of the NPA called the Manila-Rizal committee grew increasingly vocal in their opposition to this strategy. In the minds of the Manila-Rizal committee, the NPA should concentrate more on urban terrorism. In 1984 Felimon "Popoy" Lagman recast the Manila-Rizal committee as an urban terrorist hit squad. Lagman named this new group the Alex Boncayao Brigade, in memory of a committee member who was killed in the 1970s. Between 1984 and 1991, the Alex Boncayao Brigade operated as a faction of the larger NPA. Due to continuing tensions between the NPA and its faction, the two groups finally severed ties in 1991.
Since 1995, the Alex Boncayao Brigade has demonstrated decreased adherence to a strictly communist ideology. Several terrorist incidents in the late 1990s were apparently initiated as anti-globalization protests. In December 2000 the Alex Boncayao Brigade signed a truce with the Filipino military. Likely due to the ABB's government negotiations and its conciliatory implications, the NPA has begun to directly target its former ally. The NPA and ABB continue to target each others' members.