Modern? Amongst others and in no particular order:
Walter Benjamin, Franz Kafka, John Dos Passos, Sidney Bechet, Igor Stravinsky, Anton Webern, Arnold Schönberg, Marcel Duchamp, Man Ray, Kurt Schwitters, Jean Arp, Constantin Brancusi, Pablo Picasso, Fernand Léger, André Breton, Arthur Honegger, Darius Milhaud, Le Corbusier, Alberto Giacometti, Karl Kraus, Lyonel Feiningen, Johannes Itten, Walter Gropius, Paul Klee, Wassily Kandinsky, Ludwig Mies van der Rohe, Ludwig Wittgenstein, Peter Szondi, Brassaï, Robert Walser, Joseph Roth, Alfred Döblin.
Not many women in this list, I'm afraid ... there must be some that deserve inclusion though, I'm sure. First to come to mind are Anna Achmatova, Rose Ausländer and Lou Andreas-Salomé