Brazil is the location of two megacities, Brasilia and Rio de Janeiro. Brasilia is known to have had a Judge force.
Brazil was the centre of the illegal coffee trade to Mega-City One. After a major bust in 2107, Judge Joseph Dredd cynically noted that however much they cracked down "there's a lot of coffee in Brazil". 
During Judgement Day, Brasilia was overrun by zombies. Mega-City One nuked it in response.
In 2134, the uber-rich Costos suggested vacationing in "Rio".
- Brasilia was first introduced on the world map in prog 701. It had not been drawn as spreading to the large coastal cities of Sao Paulo, Salvador, or Rio - the coast is more heavily populated than the rest of the country, which bodes ill for Brazil in the Atomic War!