According to the legends, Mysore district derived its name from the city of Mysore which is also the headquarters of the District. At the every beginning the place was well known as Mahishapura, taken from a demon named Mahishasura. A very big statue of Mahishasura, after whom the city is named and a temple dedicated to Goddess Chamundeshwari on the top of Chamundi Hill near Mysore city, relate to the legend of its origin. Gangas, Rashtrakuta and Vijayanagar ruled over the region. Raja Wodeyar I (1578-1617) was the first major ruler from the Wodeyar family. He shifted his capital from Mysore to Srirangapatna in 1610 AD. In 1766, Hyder Ali Khan conquered the region. In 1947, Mysore was merged into the new dominion of independent India by Wodeyar. Mysore as a separate district came into existence on 1st November, 1956 and Jayachamaraja Wodeyar was appointed as its first governor.

Badanaval Venkatasubba Sreekantan was a former associate of Homi J. Bhabha at the Tata Institute of Fundamental Research. He is an Indian high-energy astrophysicist. The Government of India honored him with the prestigious Padma Bhushan Award in the year 1988. Mandagere Subbarao Krishnamurthy, a distinguished Kannada writer and Hindi writer is also a son of this soil.

Geographically, the district has total 6,307 sq. km. area and occupies the ranks 13th in State and 165th in India on the bases of this size. It lies at 12°30'N latitude, 76°64'E longitude and 770 m altitude. In the year 2021, there was a total 16.86% forest area of total geographical area. The district is bounded by Mandya district to the North-East, Chamrajanagar district to the South-East, Kerala state to the South, Kodagu district to the West, and Hassan district to the North. Kaveri River passes through the North-Western and Eastern parts of the district. The Krishna Raja Sagara reservoir is located in the Northern edge of the district. It receives average rainfall in the year. Red soils, lateritic soil, deep black soil, saline alluvo-colluvial soil and brown forest soil are found in the region. Quartz, magnetite, chromites, soapstone, felsites, corundum, graphite, limestone, dolomite, silicone, etc. are available in the district. Most of its rainfall occurs in the monsoon season. The actual rainfall in the district was 1018.7 mm in the year of 2021-22.

Administrative wise, the district is divided into 7 sub-districts, 19 towns and 1,199 villages. Kannada is its official language. Its district headquarters is at Mysore which is located at a distance of 144 km. from the State Capital.

Demographically according to 2011 census, the district has a total number of 6,88,422 households with a total of 30,01,127 including 15,11,600 are males and 14,89,527 are females. The density of population here is 476 persons per sq. km. The sex ratio is pegged at 985 (females per 1000 males) while the child ratio stands at 961 (females per 1000 males). As per 2011 census the percentage of major religions practiced by the people here is Hindu with 87.70% and Muslim with 9.68%. The population growth rate during the period 2001 to 2011 was 13.63% out of which 12.41% were males and 14.90% were females. According to 2011 census, the percentage of the principal languages of the region is Kannada with 80.96% and Urdu with 9.27%. In the year 2020 the number of live births in the district was 42,748 out of which 22,125 were males and 20,623 were females. In the same year the number of deaths in the district was 33,492 out of which 20,373 were males and 13,119 were females.

Economically, agriculture is the back bone of the district. Kaveri and Kabini rivers drain the district. Horticulture has also flourished in the region. Cotton, grams, groundnut, maize, rice, sugarcane, sunflower, etc. are the main agricultural crops of the district. In 1960, the first major industry was setup in Mysore. All industries in Mysore district are mainly concentrated around the city of Mysore and Nanjangud industrial estate established by Karnataka Industrial Areas Development Board (KIADB) is also remarkable. There are six industrial areas the district. Vikrant Tyres Ltd., Automotive Axles Ltd., Bharat Earth Movers Ltd. (BEML), Karnataka Silk Industries Corporation (KSIC) are some of the major industries located near Mysore city. In the year 2019-20 the gross domestic product in the district was Rs. 56,62,917 lakhs at current price and Rs. 39,75,613 lakhs at constant prices in the year 2011-2012. The net domestic product in the district during the period 2019-20 was Rs. 50,24,907 lakh at current price and Rs. 34,58,738 lakh at constant prices in the year 2011-2012. The Per Capita Income or NDDP, At Factor Cost during the period 2019-20 was Rs. 1,54,748 at current price and Rs. 1,06,516 at constant prices in the year 2011-2012.

Education wise, according to 2011 census, the literacy rate is 72.79% persons out of which 78.46% are males and 67.06% are females. The total literate population of the district is 19,62,180 including 10,63,766 are males and 8,98,414 are females. Mysore is going to be the next IT hub after Bangalore in Karnataka. The name of some of the schools in the district are Atomic Energy Central School, CFTRI School, Mysore, The Learning Curve International School (TLC), Marimallappa High School, Parkinson Memorial School, Sadvidya Pathashala, St. Joseph's High School and Sri Ramakrishna Vidyashala. It also has a number of colleges such as Government Ayurveda Medical College and Hospital, J.S.S College of Pharmacy, Karnataka State Music University, Maharani’s Science College for Women, Mysore Medical College & Research Institute, Sarada Vilas College and Vivekananda Institute, etc. Some of the other institutes are All India Institute of Speech and Hearing, Divya Deepa Charitable Trust, GSSS Institute of Management Science, Krishna Rajendra Hospital and SDM Institute for Management Development.

The district has a number of famous historical and religious places to visit. These places are Mysuru Palace, Brindavan Garden, Rail Museum, Jaganmohana Palace, Ranganathittu Birds Sanctuary, Somanathapura, Karanji Lake & Park, Kukkarahalli Lake, Bandipur National Park, Lalitha Mahal Palace and Nanjangud Temple. During the year 2016, there were 1,60,993 foreign tourists and 1,53,93,360 domestic tourists who visited above places.

The district has a number of famous personalities from different fields. Kampalapura Veeranna Narayana (KVN) is a renowned linguist, professor of Kannada language & literature and a prominent literary critic and current Chairman of the Kuvempu Bhasha Bharathi Pradikara. He was awarded by the Karnataka Sahitya Akademi. Ramachandra Rao is called ‘Father of Political Unrest’ and ‘Mysore Gandhi’. He was a great follower of Mahatma Gandhi. The Khaddar Sahakara Sangha was founded by him in the year 1925. Shadakshari Settar is an Indian professor and scholar of Indian archaeology, art-history, history of religions and philosophy as well as classical literature.