Ernakulam district was part of the ancient kingdoms, Travancore, Cochin and Malabar districts. Ernakulam had trade relations with many foreign countries including Arabs, Chinese, Dutch, Portuguese and British. The capital of Kochi kingdom was Perumpadappu Swarupam and this kingdom came into existence in the 15th century. In the 16th century, there was the emergence of the Portuguese and Dutch. The Mysore ruler Hyder Ali after conquering the Malabar district descended to Ernakulam in 1773.
The Samoothiri of Kozhikode as well as the Raja of Travancore also attacked this place. The Raja of Kochi asked the help of the British. But it led to the gradual control of the British over Kochi. Kochi became a separate state after Independence. Later in 1949 Kochi combined with Travancore to form Thiru-Kochi state. When the state of Kerala was formed, Ernakulam was a region under Thrissur district and in 1958 Ernakulam became a separate district.