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Estonian folklorist (1857–1934)
Matthias Johann Eisen (28 September 1857 – 6 August 1934) was an Estonian folklorist, and from 1920 to 1927 served as a professor of folk poetry at University of Tartu.
Eisen is best known for his thorough collection and a systematic typology of Estonian folk tales, totaling over 90,000 pages.