Rama was born on Chaitra Shuddha 9, more than 14000 years ago. Or to be precise and exact, 12240 + 2014 = 14254 (Fourteen thousand two hundred and fifty four years ago).
While in our times, lunar month of Chaitra appears during the second half of Vasanta Rutu (spring season), during Ramayana times, it was during the peak of Sharad (pre-autumn) rutu.
No wonder, Valmiki Ramayana describes lunar month of Chaitra as the time when forests were bloomed with flowers and sky covered with dark clouds and peacock dancing.
This change in the season of the year with that of the lunar month(s) is due to the astronomy phenomenon called ‘Precession of Equinoxes’. This phenomenon is behind the shift of lunar month with respect to a given season and thus a season shift of approximately one lunar month occurs every ~2000 years.
Auspicious greetings to all on the day of Rama-Navami.