There are at least four groups that go by the name of Brethren.
1) Psytrance producers Ian Summs(Phyx) and Joseph Summs(Tickets) from South Africa. They are brothers in real life.
2)Noise/Power Electronics artist from the United States.
3) Miami hardcore band Brethren who released full length album “To Live Again” on Ohev records as well as a demo, 7”, and a limited edition split CD w/ Trust No One.
4) The Aussie hip-hop crew, Brethren, are a two man team of Mistery (Matthew Peet) & Wizdm (Claude Rodriguez) from Sydney. Both individuals are veterans of the hip-hop scene in their own right.