The Antiquities of Orissa v2.c17.s1.297

v2.c17.s1.297

5. *Rāma-navamī.* The 9th of the waxing moon in the month of Cạitra was the birthday of Rāma and the memory of the auspicious event is preserved by celebrating the day by a festival. On this occasion Jagannātha, who is believed to be a later incarnation of the same personage, is dressed as Rāma and worshiped as such.