RIO BRANCO, PRELATURA nullius. — Suffragan of Belém do Pará, in the State of Pará (Brazil).
It has an area of 260,000 sq. km, with a population of 20,000, of whom 18,000 are Catholics. It has a single parish, with 6 religious priests, one male religious community, and one female religious community.
Established in 1907, on 30 August 1944 it was elevated to a prelature nullius; the Missionaries of the Consolata are currently working there.