Nuristān (Persian:نورستان), also spelled Nurestān or Nooristan, is a region in Afghanistan embedded in the south of the Hindu Kush valleys. Its administrative center is Parun. It was formerly known as Kafiristan ("land of the unbelievers") until the inhabitants were converted to Islam in 1896, and thence the region has become known as Nuristan ("Land of Light").

Today it is one of the thirty-four provinces of Afghanistan, formed in 1989 and officially established in 2001 from the northern parts of Laghman Province and Kunar Province. Its administrative center, Parun, is located in the Parun valley. Before 2001 its administrative center was situated in Laghman province due to Mujahideen control over Nuristan province.

The primary occupations are agriculture, animal husbandry, and day labor. Located on the southern slopes of the Hindu Kush mountains in the northeastern part of the country, Nuristan spans the basins of the Alingâr, Pech, Landai Sin, and Kunar rivers. It is bordered on the north by Badakhshan Province, on the south by Laghman and Kunar provinces, on the west by Panjshir Province, and on the east by Pakistan.

The Kalasha (Kalasha: Kaĺaśa, Nuristani: Kasivo) or Kalash, are indigenous people residing in the Chitral District of Khyber-Pakhtunkhwa province of Pakistan. They speak the Kalasha language, from the Dardic family of the Indo-Iranian languages, and are considered a unique tribe among the Indo-Aryan peoples of Pakistan.

They are related to the Nuristani people of the adjacent Nuristan (historically known as Kafiristan) province of Afghanistan. An autochthonous and polytheistic group like the Kalasha of Chitral, the Nuristani were forcibly converted to Islam by the 'Iron Amir' Abdur Rahman Khan in the late 19th century, while the Kalasha of Chitral maintain their own separate cultural traditions.

According to the linguist Richard Strand, the people of Chitral apparently adopted the name of the former Kafiristan Kalasha, who at some unknown time extended their influence into Chitral.^{[citation needed]}

The Nuristani people are an ethnic group native to the Nuristan region of eastern Afghanistan. The Nuristanis are a people whose ancestors practised what was apparently an ancient Indo-Iranian polytheistic Vedic religion until they were conquered and converted to Islam in the late 19th century by Emir Abdur Rahman Khan. In the mid 1890s, he conducted a campaign in Kafiristan and followed up his conquest with forcible conversions, the region thenceforth being known as Nuristan, the "Land of Light". Non-Muslim religious practices endure today to some degree as folk customs. In their native rural areas, which was referred to by the local Muslims as Kafiristan before the 19th century, they are often farmers, herders, and dairymen.

The Nuristani are distinguished from the Kalash of Chitral by their adoption of Islam and territory within Afghanistan.

The prominent and noted linguist Richard Strand, who is the sole modern authority on Hindu kush languages spent three decades in the Hindukush. He noted the following about the pre Islamic nuristani religion

Israr Ahmed (Urdu: اسرار احمد; April 26, 1932 – April 14, 2010) was a Pakistani Islamic theologian followed particularly in South Asia and also among the South Asian diaspora in the Middle East, Western Europe, and North America. Born in Hissar, (today's Haryana) in India, the second son of a government servant, he is the founder of the Tanzeem-e-islami, an off-shoot of the Jamaat-e-Islami.He has spent more than 50 years preaching Quraan.He hosted a daily show on Peace TV, a 24 hours Islamic channel broadcast internationally, and until recently^[when?] on ARY Qtv.

Ahmad was born on April 26, 1932 in Hisar (a district of East Punjab, now a part of Haryana) in India, the second son of a government servant. He graduated from King Edward Medical College (Lahore) in 1954 and later received his Master's degree in Islamic Studies from the University of Karachi in 1965. He came under the influence of 'Abul Ala Maududi' as a young student, worked briefly for Muslim Student's Federation in the Independence Movement and, following the creation of Pakistan in 1947, for the Islami Jamiat-e-Talaba and then for the Jamaat-e-Islami. Ahmad resigned from the Jama`at in April 1957 because of its involvement in the electoral politics, which he believed was irreconcilable with the revolutionary methodology adopted by the Jama'at in the pre-1947 period.