The Kingdom of Cochin, named after its capital in the city of Kochi (Cochin), was a kingdom in the central part of present-day Kerala state. It commenced at the early part of the 12th century and continued to rule until 1949, when the monarchy was abolished by the Dominion of India.
Historically, the capital of Cochin was in Kodungallur (Cranganore), but in 1341, the capital was moved to Cochin to remedy a disastrous flood. By the early 15th century, Cochin lost its ability to fully defend itself. By the late 15th century, the kingdom had shrunk to its minimal extent as a result of invasions by the Zamorin of Calicut.
When Portuguese armadas arrived in India, the Kingdom of Cochin had lost its vassals to the Zamorins, including Edapalli and Cranganore, the later of which had even been at the centre of the kingdom historically. Cochin was looking for an opportunity to preserve its independence, which was at risk. King Unni Goda Varma warmly welcomed Pedro Álvares Cabral on 24 December 1500 and negotiated a treaty of alliance between Portugal and the Cochin kingdom, directed against the Zamorin of Calicut. A number of forts were built in the area and controlled by the Portuguese East Indies, the most important of which was Fort Manuel. Cochin became a long-term Portuguese protectorate (1503–1663) providing assistance against native and foreign powers in India. After the Luso-Dutch War, the Dutch East India Company (1663–1795) was an ally of Cochin. That was followed by the British East India Company (1795–1858, confirmed on 6 May 1809) after the Anglo-Dutch War, with British paramountcy over the Cochin state.
The Kingdom of Travancore merged with the Kingdom of Cochin to form the state of Travancore-Cochin in 1950. The five Tamil-majority taluks of Vilavancode, Kalkulam, Thovalai, Agastheeswaram, and Sengottai were transferred from Travancore-Cochin to Madras State in 1956.