Parts of the Pamir and Trans-Alai mt. systems are in the east, and the highest peaks in the country are Ismoili Somoni Peak (24,590 ft/7,495 m) and Lenin Peak, formerly Kaufmann Peak (23,405 ft/7,134 m). The southeast is occupied by an arid plateau c.12,000 to 15,000 ft (3,660–4,570 m) high. The only extensive low districts are the Tajik section of the Fergana Valley in the north and the hot, dry Gissar and Vakhsh valleys in the southwest. The Amu Darya, Syr Darya, and Zeravshan are the chief rivers and are used for irrigation. Dams and irrigation projects, notably the Nurek dam and the Great Gissar Canal, have opened almost 1 million acres (400,000 hectares) of land to cultivation and also provide hydroelectric power. In addition to the capital of Dushanbe, other important cities are Khudjand, Uroteppa, and Qŭrghonteppa.

Most of Tajikistan's people are concentrated in its narrow, deep intermontane valleys. About 80% of the population is composed of Tajiks (also spelled Tadjiks or Tadzhiks), a Sunni Muslim people who speak a language virtually indistinguishable from Persian (Farsi). The rest of the people are mainly Uzbeks (15%), Russians, Kyrgyz, and others. Tajik is the official language, but Russian is widely used in government and business.

Tajikistan's economy is dependent on agriculture and livestock raising, due in part to the economic collapse that occurred with the end of Soviet rule and nearly a decade of civil strife in the 1990s. Two thirds of the population is engaged in subsistence agriculture, and some 900,000 members of the workforce are employed in Russia or other foreign countries. More than half the country's population lives in poverty, and official corruption is a serious problem.

Tajikistan's lowlands specialize in the cultivation of cotton, wheat, barley, fruit (including wine grapes), vegetables, and mulberry trees (for silk). Karakul sheep, dairy cattle, goats, and yaks are raised. The republic's mountains hold deposits of silver, gold, uranium, tungsten, zinc, lead, coal, antimony, salt, and mercury, and mining and aluminum, zinc, and lead processing are important industries. There is some petroleum. Tajikistan is well provided with hydroelectric resources, but due to poor management the country has suffered from seasonal power shortages in recent years. Other industries include light manufacturing (textiles, chemicals, and fertilizers) and food processing.

Aluminum, electricity, cotton, fruits, vegetable oil, and textiles are exported. Imports include electricity, petroleum products, aluminum oxide, machinery and equipment. Trade is primarily with the Netherlands, Russia, Uzbekistan, and Turkey. The country's economic problems and political turmoil have led Tajikistan to become an important heroin smuggling transit point.

Tajikistan is governed under the constitution of 1994. The president, who is head of state, is popularly elected for a seven-year term and is eligible for a second term. The government is headed by the prime minister, who is appointed by the president. There is a bicameral legislature. The National Assembly has 34 members; 25 are selected by local deputies, eight are appointed by the president, and one seat is reserved for the former president. Members of the 63-seat Assembly of Representatives are popularly elected. All legislators serve five-year terms. Administratively, the country is divided into two provinces and the autonomous province of Badakhshan, the easternmost section of Tajikistan.

The people of Tajikistan are probably descended from the inhabitants of ancient Sogdiana. By the 9th and 10th cent., the Tajiks had achieved much success in fruit growing, cattle raising, and the development of handicrafts and trade. The Tajik territory was conquered by the Mongols in the 13th cent. In the 16th cent., it became part of the khanate of Bukhara. By the mid-19th cent., the Tajiks were divided among several internally weak khanates.

Russia took control of the Tajik lands in the 1880s and 90s, but the Tajiks remained split among several administrative-political entities, and their territories were economically backward and were exploited for their raw materials. In the aftermath of the 1917 Russian Revolution, the Tajiks rebelled against Russian rule; the Red Army did not establish control over them until 1921. Tajikistan was made an autonomous republic within Uzbekistan in 1924; in 1929 it became a constituent republic of the USSR. In the 1930s canals and other irrigation projects vastly increased cultivated acreage as agriculture was more thoroughly collectivized; population also increased rapidly. Further expansion of irrigated agriculture occurred after World War II, especially in the late 1950s, as the area became increasingly important as a cotton producer. In 1978 there were anti-Russian riots in the republic.

In Dec., 1990, the Tajikistan parliament passed a resolution of sovereignty. The Republic of Tajikistan declared its independence in Sept., 1991, and in December it signed the treaty establishing the Commonwealth of Independent States. When the acting president sought to suspend the country's Communist party, the Communist-led parliament replaced him, and former Communist party chief Rakhmon Nabiyev was elected president in Nov., 1991. In 1992, Nabiyev was deposed by opposition militias.

An ethnically based civil war quickly erupted. Forces allied with the former Nabiyev government retook the capital and most of the country, and the parliament elected Russian-supported Emomali Rakhmonov president. Fighting between government troops, supported by the Russian army, and pro-Islamic forces, with bases and support in Afghanistan, persisted along the Afghan border despite a number of cease-fires. In the Nov., 1994, elections, which were boycotted by the Islamic opposition, Rakhmonov defeated another former Soviet leader to retain the presidency. In early 1996 there was a brief mutiny by Uzbek commanders, who seized towns in the south and west.

A peace accord was signed between the government and opposition forces in mid-1997, but some factions continued fighting. In a 1999 referendum, voters backed constitutional changes that would extend the president's term to seven years and allow the formation of Islamic political parties, and Rakhmonov was subesequently reelected. By the end of the 2000 a truce prevailed in most of Tajikistan. From 30,000 to 100,000 were estimated to have died in the fighting, and war and neglect had devastated much of the country's infrastructure, making the nation one of the poorest in the world. The government continued to mount crackdowns against any Muslims that it regards as extremists, closing a number of mosques.

Tajikistan remains dependent on help from Russia's military to preserve its tenuous stability and security, although Russian help patrolling the Afghan border ended in 2005, and Russian economic aid is also extremely important. A drought in W and central Asia in the late 1990s had particularly severe consequences in impoverished Tajikistan. The Feb., 2005, parliamentary elections resulted in a lopsided victory for the ruling People's Democratic party; the results were denounced by opposition parties, the usually progovernment Communist party, and European observers. The president's reelection in Nov., 2006, was boycotted by the main opposition parties and generally regarded as neither free nor fair. In Mar., 2006, President Rakhmonov called upon Tajiks to revive their national traditions and derussify their names; he changed his surname to Rakhmon.