History of Nagercoil
Nagercoil tells the bygones of the Kingly state it was. Temples, forts, caves, palaces, paintings and inscriptions tell the tale of the rulers, their government and their powers. It was a part of erstwhile Travancore state, but was merged with Tamil Nadu later. Nagercoil and areas surrounding were also called Nanjil Nadu.
Early History of Nagercoil
Till the 9th century, rulers of Sangam era administered many regions of Tamil Nadu including current day Nagercoil town. Then came the Pandya, Cholas and Venad Kings, who ruled this heritage land during different times in history. Venad rulers found the Travancore state and set up their palace in Nagercoil. The Palace is called Padmanabhan Palace built by Iravi Pillai Iravivarma Perumal, an important tourist attraction and archeological monument. Nagercoil is said to have influences of Jain religion too. The head priest of Nagercoil Temple in 2009 believed that the famous Nagaraja Temple of Nagercoil was once a Tamil Jain Temple. Images of Jain Tirthankaras, Mahavira and Parswanatha are carved in the temple pillars. Six Jain Idols were found in this temple and two of these are still in the Temple.
Modern History of Nagercoil
The modern history of Nagercoil revolves around the state of Travancore. Nagercoil was a part of Travancore state and took to prominence growing around Kottar. King Marthanda Verma of Travancore selected Padmanabhapuram as the capital of his state. 
During Marthanda Verma’s reign, the Dutch East India Company tried to colonize the state of Travancore calling for the Battle of Colachel in August 1741. The Dutch were defeated and could not recover from the defeat. Finally over the time the Dutch themselves assisted King Marthanda Verma in his administration and the then Dutch captain Eustachius De Lannoy was appointed the commander of Marthanda Verma’s naval force. Eustachius De Lannoy was imprisoned along with his second command but later they took up services with Travancore. This proved very beneficial to the modernization of the state of Travancore. Captain trained Travancore army in European military styles and was given Udayagiri Fort to reside, subsequently his Dutch army assisted conquering of a large part of Kerala into Travancore. They also held up the movement of Tipu Sultan’s British army in 1791, which also joined Travancore’s support later.