Jarilo (Cyrillic: Ярило or Јарило; ; ), alternatively Yarilo, Iarilo, Jarovit or Gerovit, was a major male Proto-Slavic deity of vegetation, fertility and spring, also associated with war and harvest. Sources The only historic source that mentions this deity's a 12th century biography of proselytizing German bishop Otto of Bamberg, who, during his expeditions to convert the pagan tribes of Wendish and Polabian Slavs, encountered f… (More on Jarilo)