The original Portugese capital of Brazil is a city in Bahia called Salvador. The portugese settled in Brazil in the mid 16th century and held it until they turned it over peacefully to the Brazilians in 1822.
You get a sense of the enormous wealth that the Portugese took out of Brazil during this time by visiting Salvador. They have these massive churches at almost every corner, built with the profits they made on the trade of sugar, gold, tobacco, coconuts, etc.
We visited one church called Sao Francisco (St Francis) which was covered from floor to ceiling with intricate wood carvings that were covered completely in gold leaf. I've been to a ton of churces in my day in Europe and the US and i've never seen anything like this before.
The other really cool thing about Salvador is the way the african, portugese, and native populations have combined to create a unique culture that features its own food, music, dress, etc. It's a very interesting place to visit, although its really hot this time of year.