Which work is called the originator of Western modernism?

As we all know, the American critic Edmund Wilson took 1870 as the starting point of modernist literature in his famous book "The Castle of Alxelle". Modern literature is divided into five schools: expressionism, stream-of-consciousness novels, symbolism, absurdist drama, and magical realism. Since the earliest faction of modernist literature was Symbolism, its pioneer was France's Baudelaire (1821-1867). His masterpiece is "Flowers of Evil", which can be called the foundation work of symbolism. Then we can think that "Flowers of Evil" is the originator of Western modernism. Baudelaire is considered its precursor.