In 1738, Dumas, a shrewd calculative prudent man and a lover of peace and above all one who was anxious to extend the French territory in India by smooth means, negotiated with Sahuji of Thanjavur for possession of Karaikal, the fortress of Karakalcheri and 5 village for 40000 chakras. On 14.2.1739 the French took possession of Karaikal town, the fort of Karakalcheri and 8 dependent villages. The King of Thanjavur raised the price for the town of Karaikal and the fort of Karakalcheri to 50000 chakras. He also demanded a loan of 150000 chakras without interest repayable in 3 years against the hypothecation of Mayavaram lands and an annual rent of 4000 pagodas for 5 villages. The French agreed to all the terms except for the payment of 150000 chakras which was reduced to 10000 chakras while the annual rental was reduce to two or three thousand chakras. The villages so received were Kilaiyur, Melaiyur, Puduthurai, Kovilpathu and Tirumalairayanpattinam. Subsequently 2 villages were ceded to the French. Pratap Singh who succeeded the throne renewed demand for a loan of 100000 chakra and on receipt of the first instalment of 4000 chakras he assigned 8 more villages to the French viz., Codague (Kondagai), Vanjiyur, Arimullimangalam, Niravi, Dharmapuram, Uzhiapathu, Mattakudi (probably Mathalangudi) and Polagam. Then on 12-2-1740 he sold for 60000 chakras these villages which he had assigned only the previous year for 40000 chakras. The same year he pledged Thirunallar Mahanam for 55350 chakras and also pledged 33 villages for 60000 chakras.

By a treaty signed on 12.1.1750 Pratap Singh ceded to the French 81 villages around Karaikal and cancelled the annual rent of 2000 pagodas payable for the villages. This was all the territory the French possessed around Thanjavur when they surrendered to the British in 1761. The territory then passed twice to the British control before it was finally handed over to the French in 1816/1817 under the Treaty of Paris, 1814. The formation of Karaikal national congress on 13.6.1947 and Students Congress on 31.1.1947 symbolised the first concrete expression of popular desire in Karaikal for freedom from French rule. The French ruled this district till 31st October, 1954 on which date the French flag flying atop the government house at Karaikal was lowered with due military honors before a large gathering of officials and non-officials. Thus the de facto transfer of power took place on 1st November 1954 followed by de jure transfer on 16th August 1962.