Here you can find a good explanation about the Knowledge Graph, the system used by Google to give "answers to search queries", and not "links to search keywords".
Getting the Best Summaries – by organizing and presenting information about an entity that appears within our queries in a meaningful way by studying in aggregate what people have been asking Google about each entity to be displayed in a knowledge panel.
How does Google know what to show about these things? One hint from the patent, echoed in the video, is that what people ask about in Google can determine what Google will display in the knowledge panel.
Knowledge Panels may contain information from a social networking page related to an entity as well as the other types of content I’ve mentioned above.
Where does the data come from?
According to Google, the Knowledge Graph is derived from an enormous pool of diverse data sources. Google literature has specifically made mention of the following:
2) Freebase – incidentally acquired by Google nearly 2 years ago, and also the only source in this list linked to in Google’s own literature about the Knowledge Graph.
3) Subject-specific sources such as Weather Underground, World Bank, and CIA World Factbook.
4) Google’s own immense stores of search data.
So, it could use lot of different sources, and also combine them. It evaluates not just the domain authority of content on a webpage, but even the social signals among them.
At a glance, that description seems to be taken from some paper book or touristic website: it's a romantic and promotional way to describe a country, not an encyclopedian one. But maybe I'm wrong and it's just an old Wikipedia entry.
What we know is how Knowledge Graph works in general, and the phrase you blockquoted is in more than 100k results in Google's index.
Berlin, its capital, is home to thriving art and nightlife scenes
With "" quotes (phrase match) is in only 5 results. But if you remove the quotes, you get 600k results. So, there are tons of pages where Google takes data.
By the way: if I search countries on my tld, google.it, I get every time Wikipedia entries.