Nilgiris district is a district of Tamil Nadu state with its administrative headquarters located at Udagamandalam town. Earlier, the district of Nilgiris was a special center of attraction for the Europeans because of its natural charm and extremely pleasant climate. In the year 1818, Mr. Whish and Kindersley, the two assistants of the Collector of Coimbatore helped to discover the place Kotagiri located near Rengaswamy peak. John Sullivan, the then Collector of Coimbatore was greatly interested in this region of the district. Further, he established his residence there and reported to the Board of Revenue on 31st July, 1819. The name of the district 'Nilgiris' is derived from two words 'Neelam' means blue and 'giri' means hill or mountain. Both the terms together means Blue hills. For the first time the name of the district, Nilgiris in Tamil Nadu has been found in the Shilapaddikaram. One more interesting story is also associated with the name of the district. It is believed that probably the people living in the plains at the foot of the hills gave the name Nilgiris because of the very beautiful violet colour flower, Kurinji which blooms there periodically. At the very beginning the place, Nilgiris was ruled by the Ganga Dynasty of Mysore but originally it was a region full of different tribes such as Todas, Badagas, Kotas, Kurumbas and Irulas. Slowly and gradually these tribal groups were widespread across the Nilgiri plateau. In the year 1789 the British annexed the Nilgiris and made it a part of the Coimbatore district. Nilgiris as a separate district came into existence in 1882.

C. Iyothee Thass, a distinguished Dalit, anti-caste activist and practitioner of Siddha medicine was born on 20th May, 1845 in the Nilgiris district. He is renowned as a pioneer of the Dravidian Movement.

Geographically, the district lies at 11°49'N latitude, 76°73'E longitude and 1850 m altitude. In the year 2021, there was a total 67.50% forest area of total geographical area. The district encompasses a geographical area of 2,565 sq. km. and it is bounded by Mysore district of Karanataka and Wayanad district of Kerala on the North, Coimbatore district on the South, Erode district of Tamil Nadu and Chamarajanagar district of Karnataka on the East and Malappuram district and Palakkad district of Kerala on the West. The climate of the district remains pleasant throughout the year. Most of its rainfall occurs in the monsoon season. The actual rainfall in the district was 2137.1 mm in the year of 2021-22.

Administration wise, the district is divided into 6 talukas-Udhagamandalam, Coonoor, Kundah, Kotagiri, Gudalur and Pandalur. Moreover, it comprises 18 towns and 40 villages. The administrative language in the district is Tamil.

According to 2011 census the district has a population of 7,35,394 out of which 3,60,143 are males and 3,75,251 are females. The district has a sex ratio of 1042 (females for every 1000 males). During the year 2001-2011 the population growth rate in the district was -3.51% including -4.81% were males and -2.22% were females. As per 2011 census the major religion in the district is Hindu with 77.44% of the total population. The population density in the district is 287 persons per sq. km. According to 2011 census the principal languages in the district are Tamil, Kannada and Malayalam with 49.62%, 24.45% and 17.93%. In the year 2020 the number of live births in the district was 6,097 out of which 3,119 were males and 2,978 were females. In the same year the number of deaths in the district was 5,219 out of which 3,006 were males and 2,213 were females.

The economy of the district is mainly dependent on its agricultural and tourism sectors. More than half of its population are engaged in agricultural activities in order to earn their livelihood. The chief agricultural products in the district are potato, cabbage, carrot, tea, coffee, spices, fruits, paddy, etc. The adoption of the new agricultural technologies amongst the farmers of the district helps to increase the production of various agricultural items. Eucalyptus oil produces in the district is famous in the whole country. Every year a huge chunk of revenue comes from the tourism sector of the district helps in its economy to a great extent. The district is home to several beautiful hill stations and furthermore it is very popular among the tourists who flock to them during summer. Industrially, also the district is quite well developed. There are some hydel power houses in the district includes Pykara Power House, Moyar Power House, Kundah Power House, Kateri Hydro-electric system, etc. In the year 2011-12 the gross domestic product in the district was Rs. 6,30,904 lakhs at current price and Rs. 4,08,432 lakhs at constant prices in the year 2004-2005. The net domestic product in the district during the period 2018-19 was Rs. 14,45,863 lakh at current price and Rs. 10,51,656 lakh at constant prices in the year 2011-2012. The Per Capita Income or NDDP, At Factor Cost during the period 2016-17 was Rs. 1,55,538 at current price and Rs. 1,18,970 at constant prices in the year 2011-2012.

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 85.2% including 91.72% are males and 78.98% are females. The total number of literates in the district is 5,69,647 including 2,99,447 are males and 2,70,200 are females.

M. Master Mathan, a veteran Indian politician who elected as a member of the 12th and 13th Lok Sabha from the Nilgiris Lok Sabha Constituency was born on 19th September, 1932 at Ithalur in the Nilgiris district. He is a member of the Bharatiya Janata Party.

The district has several centres of attraction which allures many travellers from different parts of the country as well as world. The Government Botanical Garden, one of the prime attractions of Ooty was established by the Marquis of Tweedale, the then Governor of Chennai in the year 1847. It covers a geographical area of twenty two hectares ascending the slopes on the hill at an elevation of two thousand four hundred to two thousand five hundred meters above sea level. The Centenary Rose Park, situated at the heart of the Ooty town covers an area of about four hectares in five terraces. This park has a great variety of roses like miniature rose, hybrid tea roses, floribunda, ramblers and many more. Adam's Fountain is the foremost tourist spot in the district and a perfect destination for recreation. Some other notable places of interest in the district are Ooty Lake-Boat House, Ketti Valley View, Dodda Betta, Pykara, Glenmorgan, etc.