Originally posted by: godisone
Oh, thanks for the explanation. It make sense now.
I think Dasharath did not split his kingdom, because he had four sons who were not the same age. Shri Ram was clearly the eldest. But Rama had twin sons, and though Kush was called the eldest, his brother Luv was still his twin, and not much younger. It would not have been fair to give the whole kingdom to Kush only, but in Dasharath's case, all of his sons were born days apart, so it was not seen as unfair to give the kingdom to Shri Ram.
And maybe Dasharath was planning to conquer new kingdoms for his other sons, but after the coronation of Shri Rama, which did not happen according to his plans. King Dasharath probably would have conquered a kingdom for Bharat, then Lakshman, and then Shatrughan, had the whole episode with Manthara and Kaikeyi not happened, and Shri Ram crowned according to plan.