Symbolism's own Wikipedia article gives a clear start ("Years active: from the 1860s") but no symmetric end date. Its own text states only that after the beginning of the 20th century the movement "had a major effect on Russian poetry even as it became less and less popular in France," describing an uneven fade in one country while it continued to influence others elsewhere, not a documented close comparable to the movement's own dated start.
What would resolve this A source naming a specific year or event as Symbolism's own agreed close, rather than an uneven, country-by-country fade with no fixed date, would resolve this.
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