Kerala Iyers or Bhattars, are Tamil Brahmins of the Indian state of Kerala — people who were residents in the Kerala region, and also people who migrated from present day Tamil Nadu in different waves starting from the medieval period onwards. The community consists of two groups - the Palakkad Iyers and Iyers of the Cochin and Travancore regions. The first wave of Iyers settled down in Palakkad district at the beginning of the medieval period. Migrations to the Travancore and Cochin regions took place mostly in the 16th and 17th centuries AD. Many of the Diwans or Prime Ministers of the princely state of Travancore were Tamil Brahmins.