In the Shakya realm, he did not receive a warm welcome as he expected (he was the son of a slave girl) and was offended when he learnt about his mother's true identity.
[5] Shortly after the Buddha's death, the Viḍūḍabha invaded the Sakya and Koliya republics, seeking to conquer their territories because they had once been part of Kosala.
Viḍūḍabha finally triumphed over the Sakyas and Koliyas and annexed their state after a long war with massive loss of lives on both sides.
The result of the Kauśalya invasion was that the Sakyas and Koliyas merely lost political importance after being annexed into Viḍūḍabha's kingdom.
[6][7] The massive life losses incurred by Kosala during its conquest of Sakya weakened it significantly enough that it was itself was soon annexed by its eastern neighbour, the kingdom of Magadha, and Viḍūḍabha was defeated and killed by the Māgadhī king Ajātasattu.