I’m tempted to make the rather bold assertion that the most interesting duo in Western literature of the 20th century is Czeslaw Milosz and Witold Gombrowicz. I say duo because you really have to take the two of them together. When Milosz zigs, Gombrowicz zags, when you’re feeling one way, Milosz expresses it for you, and when the mood shifts, there is Gombrowicz waiting in the wings with a change of pace.
The twentieth century was insane. We forget to remember that. For us, it’s what made us what we are and therefore it has taken on a sense of inevitability, even naturalness. But looking at it from the other way around, from the perspective of those who were going through it and for whom its twists and turns were anything but a foregone conclusion, the century is filled with so many shocks and amazements it is difficult to comprehend. And that, of course, was one of the great, if not the great, themes of literature from the collapse of the Austro-Hungarian empire and the outbreak of WWI to the effective finale to the 20th century in the breakup of the Soviet Union and the reuniting of Western and Eastern Europe.
Further reading: back in February Penguin released Milosz's New and Collected Poems 1931-2000. This is a huge 800-page doorstop, so if you want an easier way into Milosz try Ecco's Selected Poems 1931-2004.