European early 20th history was so dense that we tend to only remember the most spectacular events. However, the history of less influencial countries can reveal some interesting work design-wise.
After World War I, the Republic of Latvia was constituted as a parliamentary democracy. It only lasted until World War II, but that period was incredibly productive in terms of good graphic design. All great design movement of that era influenced design in the Latvian Republic, like Futurism, Bauhaus, or Dada among others.
You can read more about this topic on this article, but if you are really interested you’ll buy the book.