Nagapattinam district is a district of Tamil Nadu state with its administrative headquarters located at Nagapattinam town. The district got its name from its headquarters town, Nagapattinam. Nagapattinam is taken from the two words Nagar and pattinam. The first term Nagar refers to the people from Sri Lanka who settled in this place and the second term pattinam means town. It is believed that during the reign of Cholas, the place was one of the prominent ports in the world and at that time the place was popularly known as Cholakula Vallipattinam. Ptolemy, an eminent Greco-Egyptian writer called Nagapattinam as Nikam, one of the most important trade centres of the ancient Tamil country. The urn burials in and around the city indicates the fact that the human habitation in this place was started since the Sangam period. The early writers and the Portuguese used to call Nagapattinam as "the city of Coromandel". Appar and Tirugnanasambandar, the 7th-century saint poets refer to the place as Nagai in their verses in “Tevaram”. Later the place was ruled by Pallavas, Portuguese, Dutch and British during different periods of time. For the first time the place fell into the hands of the British in the year 1781 after the two naval battles between British and French fleets were fought off the coast of Negapatam. After some time the town was taken by the British from the Dutch in 1781. When the Dutch and British reached a peace agreement in 1784, Nagapattinam was formally ceded to the British. Whenever, someone unfolds the history of Tamil Nadu, it is obvious to remember the Indian Ocean earthquake of 2004 which not only took away number of lives but also affected the whole place very badly. Nagapattinam as a separate district came into existence on 1st January, 1997.

Shiyali Ramamrita Ranganathan, an illustrious mathematician and librarian was born on 12th August, 1892 at Shiyali in the district. He is also considered to be the father of library science, documentation, and information science in India.

Geographically, the district lies at 10°77'N latitude, 79°83'E longitude and 1 m altitude. In the year 2023, there was a total 7.09% forest area of total geographical area. The district encompasses a geographical area of 2,569 sq. km. and it is bounded by Cuddalore district on the North, Bay of Bengal on the South and East and districts of Tiruvarur, Thanjavur and Ariyalur on the West. Most of the rainfall in the district occurs in the monsoon season. The actual rainfall in the district was 1534.2 mm in the year of 2024-2025.

Administration wise, the district is divided into 8 talukas namely Kilvelur, Kuthalam, Mayiladuthurai, Nagapattinam, Sirkali, Tharangambadi, Thirukkuvalai and Vedaranyam. Moreover, it comprises 14 towns and 491 villages. The administrative language in the district is Tamil.

According to 2011 census the district has a population of 16,16,450 out of which 7,98,127 are males and 8,18,323 are females. The district has a sex ratio of 1025 (females for every 1000 males). Furthermore, the district has projected population of 19,71,245 comprising 9,74,767 males and 9,96,478 females for the year 2026. According to the National Family Health Survey (NFHS-5, 2019–21), the district has an estimated sex ratio of 1,148 females and a child sex ratio of 894 females per 1,000 males. During the year 2001-2011 the population growth rate in the district was 8.57% including 7.99% were males and 9.14% were females. As per 2011 census the major religion in the district was Hindu with 88.78% of the total population. The population density in the district is 629 persons per sq. km. According to 2011 census the principal language in the district is Tamil with 99.42%. In the year 2023 the number of live births in the district was 6,099 out of which 3,098 were males and 3,001 were females. In the same year the number of deaths in the district was 5,711 out of which 3,340 were males and 2,371 were females.

The economy of the district is mainly dependent on agriculture. More than half of its population are engaged in agriculture in order to earn their livelihood. The chief agricultural products in the district are rice, groundnut, pulses, ginger, sugarcane, cotton, etc. The adoption of the new agricultural technologies amongst the famers of the district helps to increase the production of various agricultural items. Fishing is a source of extra income for its natives. Industrially, also the district is quite well developed but its industrial activity is very limited. The foremost industrial activities in the district are household, tailoring, embroidery, plastic wire and metal manufacturing, etc. Every year a huge chunk of revenue comes from the industries in the district helps in its economy to a great extent. Cauvery Basin Refinery, a subsidiary of Chennai Petroleum Corporation Limited (CPCL) is situated near to the Nagapattinam was established in the year 1993 is a major contributor to the economy of the district. In 2006 the Ministry of Panchayati Raj named Nagapattinam as one of the country's 250 most backward districts and currently receiving funds from the Backward Regions Grant Fund Programme (BRGF). In the year 2023-2024 the Gross Domestic Product in the district was Rs. 16,25,353 lakh at current price and Rs. 8,36,735 lakh at constant 2011-2012 prices. The Net Domestic Product in the district during the period 2023-2024 was Rs. 14,88,419 lakh at current price and Rs. 7,43,970 lakh at constant 2011-2012 prices. The Per Capita Income or NDDP, At Factor Cost in the district during the period 2023-2024 was Rs. 1,99,792 at current price and Rs. 99,864 at constant 2011-2012 prices.

The district is well-known as an abode of several reputed educational institutions. It provides a platform for higher education. As per 2011 census the literacy rate in the district is 83.59% including 89.79% are males and 77.58% are females. The total number of literates in the district is 12,13,008 including 6,40,916 are males and 5,72,092 are females. In addition, according to the Periodic Labour Force Survey (PLFS) for the period July 2023-June 2024 estimated literacy rate in the district is 75.71% including 83.74% are males and 70.32% are females (Age 7 Years and Above).

Muthuvel Karunanidhi, a famous Indian politician who has served as the Chief Minister of Tamil Nadu on five different occasions was born on 3rd June, 1923 at Thirukuvalai in the district. He has been acting as a veteran leader of the Dravida Munnetra Kazhagam (DMK) since the death of its founder, C.N. Annadurai, in 1969.

The district has several centres of attraction which allures many travellers from different parts of the country as well as world. Kayarohanaswami Temple, located in the Nagapattinam is a Hindu temple dedicated to Lord Shiva. From the 6th century CE this temple with some inscription of sacred verses of Tevaram has been present in the Nagapattinam. Nagore Durgha, a 16th-century minaret located at Nagore in the district is one of the most significant pious places of the Nagapattinam town. Kanduri festival, a 14 days event celebrated for the annual anniversary of the saint Hajrath Shahul Hamid is the prime attraction of this place. Velankanni, another distinguished pilgrimage centre located at a distance of 10 km. from Nagapattinam town is renowned for the Basilica of Our Lady of Good Health, a Roman Catholic Church which was built during the 17th century. Some other notable temples in the district are Sikkal Singaravelan Temple at Sikkal, Vedaranyeswarar Temple at Vedaranyam, Ettukudi Murugan Temple, Koothanur Maha Saraswathi Temple, Soundararajaperumal Temple, etc. During the year 2024 there were 46,33,181 domestic tourists and 34,799 foreign tourists who visited these places of the district.