Waziristan (Pashto and , "land of the Wazir") is a mountainous region covering the former FATA agencies of North Waziristan and South Waziristan which are now the districts of the Khyber Pakhtunkhwa province of Pakistan. Waziristan covers around . The area is populated by ethnic Pashtuns. It is named after the Wazir tribe. The language spoken in the valley is predominantly Pashto of the Waziri dialect. The region forms the southern part of Pakistan's former Federally Administered Tribal Areas, which is now part of the Khyber Pakhtunkhwa province.
The 16th-century Pashtun revolutionary leader and warrior-poet Bayazid Pir Roshan, who wrote the oldest known book in Pashto, was based in Kaniguram, Waziristan.
The name "Waziristan" is associated with a Pashtun tribe called the Wazir which is predominantly settled in the North Waziristan region.
Waziristan lies between the Kurram River and the Gomal River. It borders the Kurram Agency in the north, Bannu in the northeast, Tank in the east, Dera Ismail Khan in the southeast, Sherani and Musakhel districts of Balochistan in the south and Khost, Paktia, and Paktika provinces of Afghanistan in the west.
Waziristan is divided into two districts: North Waziristan and South Waziristan. According to the 2017 census report, the population of North Waziristan was 543,254 while that of South Waziristan was 674,065. The two parts have quite distinct characteristics, though both are inhabited by the Wazir and Mahsud (or Maseed) tribes. They have a reputation as formidable warriors.
The British entered Waziristan in 1894, when the boundary with Afghanistan, known as the Durand Line was determined. They divided Waziristan into two agencies, North Waziristan and South Waziristan; they also introduced a regular system of land record and revenue administration for the most fertile part of the Tochi valley. After the British military operations, a Political Agent for South Waziristan was permanently appointed with its headquarters at Wanna; another was appointed for North Waziristan with headquarters at Miranshah.