On the basis of Careful analysis of language, style and content, J.L. Brockington {1984} has identified five distinct chronological and cultural stages in the development of Ramayana . The epic started taking shape as an oral composition during the 4th-5th centuries BCE (stage 1}. The story emphasised the heroic element and its geographical horizons were limited .The material culture and social structure represented were relatively simple , the religious ideas and practices closer to those of the Vedas than the Puranas .
In 2nd stage dated 3rd century BCE-1st century CE, there was a shift from heroic to the aesthetic element. The geographical awareness of the text expanded eastward into the lower Ganga valley. References to social and economic life, such as the emphasis on the chastity of women and the description of cities and trade caravans, suggest increasing levels of class stratification and subordination of women. The power of the king was emphasised and welfare had become more elaborate. The story was imbued with a religious significance.
Stage 3rd belongs to the 1st-3rd centuries CE. By then urbanisation had spread to many new areas. The division of society into four varnas was emphasised. The king was exalted as a protector of his people and the social order. The subordination of women has increased. Vedic gods such as brahma and Indra were still important, but Vishnu or Shiva had appeared on the scene and were exalted. Books 1st and 7th were added to the Epic during this period.
In stage 4th (4th -12th centuries), the religious and aesthetic emphasis increased. Descriptions of society underlined the pre- eminence of the Brahmanas and the low position of the Shudras and out-castes. References to inauspiciousness of widows and the practice of sati(the ritual of self-immolation of widows) reflect the increasing subordination of women. Vishnu and Shiva emerged as supreme gods in a religious milieu marked by temple worship and pilgrimage. The trends visible in the fourth stage were strengthened from the 12th century onwards (stage 5th).
Apart from these different cultural stages, Brockington also identifies corresponding changes in the delineation of the main characters of the story. For instance, he argues that in stage 1st, Rama was essentially considered an exemplary human and that it was towards the end of the stage 2nd that he started being conceived as a divine. In stage 3rd , Rama’s victory over Ravana came to be presented as a victory of dharma(righteousness) over evil. Although there are references to devotion to Rama in this stage, the divine character of Rama, his association with Vishnu, and his description as an incarnation (avatara) of Vishnu are regular features of stage 4th and 5th.
Brockington talks of the transformation of a heroic epic into a religious epic. However, Pullock (1991:52) argues that the Ramayana was provided by the idea of Rama’s divinity from the very outset.
All this information has been gathered from Upinder Singh’s book: a history of ancient and early medieval India.