Germans in Australia do speak English. Also, I don't think the number of Germans who mostly meet Germans everyday is big. All my German (and French, and Russian) friends in Australia had girlfriends from other places. But sorry, communautarism is visible, generalizations over one's communautarism is frequent but communautarism itself isn't that much.

This isn't a surprise. There's a reason large cities have Chinatown, Little Italy, etc. Immigrants are more comfortable keeping their lives mostly within their own community that shares the same language and cultural elements. While I don't think it's all that healthy to avoid integrating with the society you move into, it's understandable to see people take the easy/comfortable route. Hell, I'd probably wind up doing the same.

I have a Greek acquaintance who lives in my city's unofficial Greek neighbourhood. Everything from groceries to bakeries and cafés, it's all Greek and he doesn't like to stray much from his routine in these shops. All the owners and patrons know each other personally. They get to feel like they're still back home. It keeps them sheltered a bit too much from the rest of us, but hey - they have a real community versus me that doesn't know the first name of anyone that serves me in any of the shops I frequent.

People move somewhere for a reason: most migrants (they are white so they are usually referred to as expats) in my neigborhood in south Spain are Brits who came for the weather and low prices: a lot of them simply want to live in a cheaper and sunnier UK. They do not want to integrate as that is not why they came. Same for the Germans; we have an entire town where everything is in German. Some come for the different lifestyle and Spanish culture; those integrate fast but it is a minority.

This is a more general phenomenom, like tends to hang out with like, not necessarily out of bigotry towards the un-likes, but just out of familiarity. It's really "seperate but equal" all over again.

Honestly, it just comes down to being open minded, which has to happen on an individual level. I'm open minded by necessity, because there are very few of my race in the USA, much less my current city.

I suppose typically first generation migrants seldom adjust culturally fully to their home country, and only the second generation become truly native?

Integrated to what exactly? You are never going to be integrated with people that want you to speak the local language, even if you do speak it. The thing is, once you leave your country, you are an expat, an expat doesn't do well with people that want to force their local/close minded way of doing things on you.

There are values that are the same across all Europe and those should be the focus of integration. Learning local language is not one of them.