On February 21, 1978, Mohammad Daud leaves Kabul for Belgrade on an official visit to Yugoslavia.
Three days later, a trial of 25 people accused of plotting to assassinate President Daud begins in Kabul.
On April 17, Mir Akbar Khaibar, one of the founders of the People's Democratic Party of Afghanistan (PDPA), is assassinated in Kabul.
PDPA leader Hafizullah Amin, his arrest apparently imminent, contacts PDPA members in the armed forces and devises a makeshift but successful coup.
On April 27, 1978-7 Saour, 1357 AH, according to the Muslim calendar-Daud's five-year-old Republican regime is overthrown.
On April 29, the government radio reports that Defense Minister Ghulam Haidar Rasuli, Interior Minister Abdul Qadir Nuristani, and Vice President Saeed Abdulillah have been killed in the coup, along with President Daud and his brother Mohammad Naim.
The next day, a "Revolutionary Council" is proclaimed.
Nur Mohammad Taraki is elected president of the Revolutionary Council, prime minister of the country, and secretary general of the combined PDPA.
Babrak Karmal, a Banner leader, and Hafizullah Amin are elected deputy prime ministers.
On May 6, Taraki declares Afghanistan "nonaligned and independent." The leaders of the new government insist that the Soviet Union does not control them.
They proclaim their policies to be based on Afghan nationalism, Islamic principles, socioeconomic justice, nonalignment in foreign affairs, and respect for all agreements and treaties signed by previous Afghan governments.
Unity between the People's and Banner factions rapidly fades as the People's Party emerges as the dominant wing, particularly because their major base of power lies in the military.
Karmal, Najibullah, and other selected Banner leaders are sent abroad as ambassadors, and the government systematically purges any Banner members or others who might oppose the Taraki regime.
Najibullah briefly serves as ambassador to Iran and then goes into exile in Eastern Europe.
Employing classic Marxist-Leninist rhetoric, the government announces its reform programs, including the elimination of usury, changes in marriage customs, equal rights for women, land reforms, and administrative decrees.
The highly conservative people in the countryside, familiar with Marxist broadcasts from Soviet Central Asia, assume that the People's Party is Communist and pro-Soviet.
The reform program-which threatens to undermine basic Afghan cultural patterns as well as deeply rooted Islamic traditions-and political repression antagonizes large segments of the population, but major violent responses do not occur until a major uprising in eastern Afghanistan's Nuristan region late in the summer of 1978.
Other insurgencies, largely uncoordinated, spread throughout all of Afghanistan's provinces, and periodic explosions rock Kabul and other major cities.
On August 18, Kabul Radio announces that a plot to overthrow the government has been foiled and Defense Minister Abdur Quadir has been arrested for his role in the plot.
On August 23, the politburo of the PDPA orders the arrest of Planning Minister Sultan Ali Kishmand and Public Works Mohammad Rafi for their parts in the conspiracy.
Pakistan's Chief Martial Law Administrator Mohammad Zia-ul Haq meets with Taraki at Paghman, near Kabul, on September 9.
On September 22, Taraki dismisses six ambassadors who had been appointed in July; all are members of the Parcham section of the PDPA.
In October, the green, red and black national flag is changed to an all-red field, after the Soviet fashion.
A five-pointed star again surmounts the new national device, in gold.
On December 3, Taraki arrives in Moscow for talks with Soviet leaders.
Two days later, the two nations sign a 20-year treaty of friendship and cooperation.