Conversation so far:
How were the Sinhalese kingdoms formed?
Tambapanni.
Who or what are the Tambapanni?
landed on the island at a site believed to be in the district of Chilaw, near modern-day Mannar, and founded the Kingdom of Tambapanni.

Question: Is this were the Sinhalese live today?
Self-contained rewrite: Is Mannar where the Sinhalese people live today?