Afghanistan, to the 1930s

Officially, Afghanistan was neutral during the Great War, and it was receiving subsidies from the British. Soon after the war, Afghanistan's monarch, Amir Habibullah Khan, age 68, was assassinated while on a hunting trip. At the time of the assassination his son, Amanullah Khan, was governor of Kabul and in control of the army and the treasury. He is suspected of having organized his father's death. He seized power and imprisoned relatives with competing claims to the succession, and he won the allegiance of most tribal leaders. Amanullah Khan became "King of the God granted kingdom of Afghanistan and its dependencies" on 28 February 1919. Amanullah Khan had other ambitions. On 3 May 1919 he led a surprise attack against the British on Afghanistan's frontier with India – while the British were under pressure from unrest in India and suffering involvement in Europe's Great War.

Military skirmishes between the British and Afghani became a stalemate. In May 1921 Afghanistan and the Soviet Union signed a Treaty of Friendship. In 1921, Britain and Afghanistan agreed to an armistice. Another agreement, the Treaty of Rawalpindi, signed on 19 August 1919 was amended on 22 November 1921, with Britain recognizing Afghanistan's independence and agreeing that the border of its empire in India would never extend past Khyber Pass. Afghanistan's Independence day became the 19th of August.

Amanullah was a popular ruler, and he used that popularity to attempt modernization. He created cosmopolitan schools for both boys and girls and overturned strict dress codes for women. He increased trade with Europe and Asia. In 1924, reaction against westernization produced the Khost Rebellion by the Mangal Pashtun tribe, to be joined by other tribes. The rebellion was suppressed in 1925, but conservative Muslim opposition remained. In late 1927 Amanullah traveled to Europe and in his absence opposition to his rule increased. An uprising in Jalalabad culminated in a march to Kabul. Many soldiers deserted the king. In 1929, Amanullah abdicated and thereafter remained in exile in Italy and then in Switzerland.

In 1929 Amanullah's cousin, Mohammed Nadir Shah, became King of Afghanistan and quickly abolished most of Amanullah's reforms. He tried to rebuild an army, but his forces remained weak vis-a-vis religious and tribal leaders. His rule was challenged by uprisings, and that year a Soviet force crossed the border in pursuit of an Uzbek leader whose forces had been harassing the Soviets from his sanctuary in Afghanistan. Nadir Shah's army managed to drive the Uzbek army out of Afghanistan and to subdue most of the uprisings, and in 1931 he promulgated a new constitution that instituted a royal oligarchy. He placated religious factions with a constitutional emphasis on orthodox Islamic principles. He also started road building. He imported what was then modern communications technology, a banking system, and he started long-range economic planning.

On November 8 1933, while visiting a high school in Kabul and distributing awards at the end of a soccer game, Nadir Shah was shot dead by a teenager named Abdul Khaliq, a Shia of the Persian-speaking Haraza ethnicity. After being tortured, Khaliq, his friends, his mother, his father, his uncle, brother and his seven-year-old sister were hanged. Khaliq was cut into pieces starting from the cutting of his fingers, nose, ear and tongue until he bled to death.

Nadir Shah was succeeded by his 17-year-old son, Mohammed Zahir Shah, who was to reign during a relatively peaceful forty years to 1973. The son was declared the "Father of the Nation," and he was to live to 2007 and the age of 92.