Janmashtami, Hindu festival celebrating the birth (janma) of the god Krishna on the eighth (ashtami) day of the dark fortnight of the month of Bhadrapada (August–September). The number eight has another significance in the Krishna legend in that he is the eighth child of his mother, Devaki.Janmashtami, Hindu festival celebrating the birth (janma) of the god Krishna on the eighth (ashtami) day of the dark fortnight of the month of Bhadrapada (August–September). The number eight has another significance in the Krishna legend in that he is the eighth child of his mother, Devaki.