German outpost in Brazil

The webmaster of Human Stupidity mentioned to me that there is a small region, in Southern Brazil, that was settled by Germans back in the 19th century.  What is remarkable about it, especially the city of Pomerode, is that a majority of the population continues to speak the Pomeranian German of their ancestors.  From the Wikipedia article about it:

Pomerode was founded by PomeranianGermans in 1861 and is considered the “most typically German of all German towns of southern Brazil”.
One very remarkable characteristic about Pomerode is the fact that Pommersch is still being preserved by the majority of the local population.
In Pomerode, as in some other localities in southern Brazil (Santa Maria de Jetibá, Espírito Santo, among them), the German language is not a foreign language, but a Brazilian linguistic regionalism.
For a good part of the 20th century, the Brazilian government did not encourage people to speak the German language. As a matter of fact, at times it was actively repressed and prohibited, like during Getúlio Vargas‘s presidency. Today on the other hand the German language is part of the curriculum in local schools and strongly encouraged by the local governments throughout southern Brazil.

The largest proportions of whites, in Brazil, can be found in the South.  Hence, the standard of living tends to be higher there and crime is lower.  According to Wikipedia, 79% of the South region of Brazil is white.  In Pomerode, the percentage is in the 90’s.  So it is no surprise that blacks and mulattoes trickle in from the North to take advantage of this.  One of the tragedies of the political entity known as the “state” is that it tends to homogenize minority populations within its arbitrary boundaries.  Since the regional population lacks the autonomy to restrict immigration into its own territory by political/military means, it is left to the mercy of economic trends.  The minority population must, in a sense, choose between retaining their own national character by remaining poor and backward (so that few outsiders would want to move there), or improving their standard of living and losing their ethnic/racial identity due to the migration of undesirables.
Though there have been secessionist movements in the South of Brazil, it would seem that the odds of success are slim to none.  The only apparent options available to them, to preserve their own identity into the future, would be continued underground intimidation of intruders or to convince the central government to restrict the movement of people into their region (as the Indian government does with some of its tribal areas).  Realistically, I doubt there is any chance that a Western government would make any sort of accommodation for white groups within its territory.  The exclusion of the Amish from social security taxes was a rare exception and was by virtue of their religion, not their race.
If I were a native of Pomerode, I would start a campaign to inform outsiders that, although their tourist money and visits are welcome, they are not welcome to stay and settle.  Billboards could say, “Welcome to Pomerode!  Enjoy yourself – and then go on home”.  This sort of campaign has been done before – but the details escape me at the moment.