Born in Iraq in 1903, Barzani belonged to the Kurdish minority concentrated mainly in the northern part of the country. Due to persecutions and attempts at Arabization of the Kurds by the government since the 1920s, he chose to respond by leading, along with his brother Shaykh Ahmad, an armed rebellion starting in 1931; however, they were defeated and exiled to Sulaymaniyah in northern Iraq. When their second insurgency, carried out in 1943, was crushed, they had to flee to northern Iran, where they founded the KDP (Kurdistan Democratic Party, the first militant party for their people). In 1946, with Soviet support, the Kurdish Republic of Mahabad was established. It lasted until the end of the same year when the Red Army withdrew, allowing Iranian forces to drive Barzani and his guerrillas (the peshmerga) into exile first in Iraq and later in the USSR.

In 1958, following the fall of the monarchy in Iraq, Barzani and his followers were able to return home, but their demands were excessive for the new government led by Prime Minister Abd al-Karim Qasim, who then ordered a military offensive. Thanks to their guerrilla tactics, Barzani and the peshmerga resisted until 1970 when a ceasefire was reached (meanwhile his brother had passed away). Baghdad then initiated negotiations to grant autonomy to the Kurds, even recognizing their language as the country's second official language. However, the talks failed, and Barzani led another insurgency, this time supported by the US and Iran. The latter, however, switched sides to support Iraq the following year after striking a new agreement. The government in Baghdad was able to strengthen its position while Barzani had to flee to the US where he died of cancer in 1979. Despite his death, his legacy survived for years, and the peshmerga he led continued to challenge the Iraqi government until the US invasion in 2003.