Tadzhikistan is the most common alternate spelling and is widely used in English literature derived from Russian sources.
Cultures in the region have been dated back to at least the 4th millennium BCE, including the Bronze Age Bactria–Margiana Archaeological Complex, the Andronovo cultures and the pro-urban site of Sarazm, a UNESCO World Heritage site.
A civil war was fought almost immediately after independence, lasting from 1992 to 1997.
The territory that now constitutes Tajikistan was previously home to several ancient cultures, including the city of Sarazm of the Neolithic and the Bronze Age, and was later home to kingdoms ruled by people of different faiths and cultures, including the Oxus civilisation, Andronovo culture, Buddhism, Nestorian Christianity, Zoroastrianism, Manichaeism and Islam.
The area has been ruled by numerous empires and dynasties, including the Achaemenid Empire, Sasanian Empire, Hephthalite Empire, Samanid Empire, Mongol Empire, Timurid dynasty, the Russian Empire, and subsequently the Soviet Union, upon whose dissolution in 1991 Tajikistan became an independent nation.
Some authors have also suggested that in the 7th and 6th century BCE parts of modern Tajikistan, including territories in the Zeravshan valley, formed part of Kambojas before it became part of the Achaemenid Empire.
After the region's conquest by Alexander the Great it became part of the Greco-Bactrian Kingdom, a successor state of Alexander's empire.
While constitutionally a secular state, Islam is practiced by 98% of the population.
The Gorno-Badakhshan Oblast of Tajikistan despite its sparse population is home to incredible linguistic diversity where Rushani, Shughni, Ishkashimi, Wakhi and Tajik number among the languages spoken. It has a transition economy that is highly dependent on remittances, aluminium and cotton production.Tamerlane created the Timurid dynasty and took control of the region in the 14th century.Modern Tajikistan fell under the rule of the Khanate of Bukhara during the 16th century and with the empire's collapse in the 18th century it came under the rule of both the Emirate of Bukhara and Khanate of Kokand.Like all other Central Asian neighbouring states, the country, led by President Emomali Rahmon since 1994, has been criticised for authoritarian leadership, lack of religious freedom, corruption and widespread violations of human rights by a number of non-governmental organizations.Tajikistan is a presidential republic consisting of four provinces.The Samanid Empire, 819 to 999, restored Persian control of the region and enlarged the cities of Samarkand and Bukhara (both cities are today part of Uzbekistan) which became the cultural centres of Iran and the region was known as Khorasan.