Is it the truth, people from northern Portugal?

Not exactly but there are many jokes about the folks from the Alentejo region, for example. If you take jokes as looking down on someone, they could say they are looked down upon. On the other hand, the northeastern region of Tr�s-os-Montes was once relatively isolated, so maybe they were looked down. Finally, there's an old rivalry between Porto and Lisbon. Liss tend to think that "Lisbon is Portugal and all the rest is mere landscape" but in opinion Porto should be the capital, lol. If you ask me, Liss earn bigger wages and work less and worse just because the government is there. Now, if only our governments ever did something worthwhile...