Socio-economic background The middle Ganga valley was a
comparatively new ecological situation for the settlers, whether those of the
Painted Grey Ware or of the Black-and-Red Ware cultures, particularly with
rice cultivation becoming the major agricultural activity.
                           RICE CULTIVATION
  The yield of rice is higher per acre than that of wheat; rice cultivation
  could therefore have supported a larger number of people. The
  demographic rise in the Northern Black Polished Ware period, suggested
  by the increase in the size of settlements and their frequency, would have
  required bigger yields to feed the growth in the population.
     Where land, labour and irrigation were made available the production of
surplus was feasible and this could support a larger population or intensify
the social base of stratification. There are references to the dasa-karmakaras
(slaves and labourers) in the fields of the raja-kulas (the land-owning
kshatriya clans) and there is evidence of economic disparity among social
strata. This dual stratification of gana-sanghas into dasa-karmakaras
employed by the raja-kulas, with an absence of grihapatis (or gahapatis as
they are called in Pali texts), is prior to private ownership.
     Gahapatis are occasionally mentioned in the sources related to the gana-
sanghas. but rarely as agriculturalists. Gahapatis are more evident in the
monarchies of the middle Ganga valley.
                     MONARCHY VS REPUBLIC
  In the middle Ganga valley, in contrast to the western Ganga valley, the
  use of land and irrigation in itself required not only intensive labour but
  also the organisation of labour on the lines of cooperative interaction.
  Further contrast between the two areas indicate differences in the social
  structure of the gana-sangha chiefdoms and the kingdoms in the middle
  Ganga valley. The preconditions were similar and yet the state system
  evolved more clearly under the aegis of a monarchical form. A
  comparison between the gana-sanghas            and the monarchies may serve to