Malayali kingdom of the central Kerala coast, known as Perumpadappu Swaroopam, which emerged after the fall of the Later Cheras and became a pivotal spice-trade power under successive Portuguese, Dutch and British protection.
A Portuguese (1503) then Dutch (1663) protectorate and a tributary of Mysore (1776-1791); passed under British paramountcy and acceded to the Dominion of India in 1949.
Classic detailed history of Kerala including the Cochin (Perumpadappu) kingdom; verified via Open Library.
Standard one-volume survey covering the Cochin state; verified via Open Library.