Thrissur played a main role in the political history of South India. Thrissur was ruled by the Cheras and their capital was at Vanchi. During the ancient times, Thrissur had good trade relations with foreign countries. Kodungalloor in Thrissur is a place in which the communities Christians, Jews and Muslims took shelter. Thrissur during the period from 9th century to 12th century was under the rule of Kulasekharas of Mahodayapuram. After that period, there was the growth of Perumpadappu Swarupam. There was the supremacy of Perumpadappu Moopil who was popularly called as Kerala Chakravarthi.
During the 14th and 15th century a major part of Thrissur was under the control of the Calicut Samoothiris. There was a rise in the power of Portuguese which continued until 17th century. Then there was the emergence of the Dutch and European powers. In 1790, Raja Rama Varma who was popularly called as Shakthan Thampuran became the ruler of Cochin. He played a main role for the defeat of the feudal Nair chieftans and with that there was a rise of the Royal power. There were Namboothiri and Menon communities also in Thrissur. The Thrissur taluk was under the control of Yogiatirippads who were the heads of the Vadakkunnathan and Perumanam Devaswoms.
In 1919, a committee of the Indian National Congress functioned. There were participants in the Civil Disobedience Movement of 1921. The nationwide movement for temple entry and removing untouchability was mainly started in Thrissur. A memorable event in the field of national movement is the Guruvayur Satyagraha.