The UDA West Belfast Brigade is the section of the Ulster loyalist paramilitary group, the Ulster Defence Association (UDA), based in the western quarter of Belfast, in the Greater Shankill area. Initially a battalion, the West Belfast Brigade emerged from the local "defence associations" active in the Shankill at the beginning of the Troubles and became the first section to be officially designated as a separate entity within the wider UDA structure. During the 1970s and 1980s the West Belfast Brigade was involved in a series of killings as well as establishing a significant presence as an outlet for racketeering.
The Brigade reached the apex of its notoriety during the 1990s when Johnny Adair emerged as its leading figure. Under Adair's direction the West Belfast Brigade in general and its sub-unit "C Company" in particular became associated with a killing spree in the neighbouring Catholic nationalist districts of west Belfast. With Adair and his supporters suspicious of the developing Northern Ireland peace process and the Combined Loyalist Military Command ceasefire of 1994, the West Belfast Brigade increasingly came to operate as a rogue group within the UDA, feuding with rival loyalists in the Ulster Volunteer Force before splitting from the UDA altogether in late 2002. Ultimately Adair was forced out and the brigade was brought back into the mainstream UDA. It continues to organise, albeit with less significance than in its heyday. Matt Kincaid is the incumbent West Belfast Brigade leader and under his leadership the brigade has again become estranged from the wider UDA.
The origins of the UDA lay in west Belfast with the formation of vigilante groups such as the Shankill Defence Association and the Woodvale Defence Association. The latter, formed by Charles Harding Smith, became the largest of a number of similar groups and was instrumental in the establishment of the UDA in September 1971, having begun military training of its members two months earlier. In 1972, when Jim Anderson was serving as acting chairman of the UDA, a West Belfast battalion was formed as a separate part of the UDA, such was the volume of membership within the area. The battalion was divided into three separate companies: A Company, which was based on the Highfield estate with some members in Glencairn, B Company which covered the Woodvale area, and C Company for the Shankill Road itself. Battalions covering the other three areas of Belfast as well as South East Antrim and North Antrim and Londonderry were formed soon afterwards and before long these were re-designated as brigades after the UDA experienced a rush of members.