South Korean President Yoon Suk-yeol’s decision to declare martial law has sparked the East Asian country’s biggest political crisis in decades and sent shockwaves around the world.

Yoon imposed the emergency law after accusing the main opposition party, the Democratic Party, of being sympathetic to North Korea and engaging in subversive activities.

Hours later, Yoon had to give in after opposition MPs forced their way past security forces into parliament. All 190 deputies present in the 300-member assembly voted unanimously to lift the martial law order.

Calls for the impeachment of Yoon, leader of the conservative People Power Party, are growing as the country reels from political turmoil.

But few countries with advanced economies have as long a history of martial law and scandal-plagued governments as South Korea.

What is martial law?

Martial law ensures the temporary rule of military authorities in emergencies. But most young South Koreans have no memory of the last introduction in the late 1970s.

“People are texting and asking, ‘What kind of martial law is this?’ Nobody saw this coming,” Al Jazeera’s Eunice Kim, reporting from Seoul, said on Tuesday.

While Yoon’s brief imposition of martial law was the first of its kind in four decades, South Korea has a long history of military rule.

“South Korea’s democracy is still very young, only beginning in 1988 after nearly three decades of authoritarian rule, most of which was a very harsh dictatorship under three different dictators,” said Katharine Moon, a political science professor at Wellesley College in Massachusetts. United States, Al Jazeera said.

History of Martial Law in South Korea

August 15, 1948

The Republic of Korea, as South Korea is officially called, was founded in 1948 after the division of the Korean Peninsula into South and North Korea. The staunch anti-communist Syngman Rhee became its first president and imposed martial law to crack down on communists.

The Korean War began on June 25, 1950, when North Korean troops invaded South Korea in an attempt to reunite the two countries. Fighting raged for three years between Chinese-backed northern troops and U.S.-backed United Nations forces. By the time the armistice was signed in 1953, the war had claimed an estimated two million lives.

In 1960 there were protests against electoral corruption, also called the April Revolution. Rhee reimposed martial law. But as protests grew, Syngman was forced to resign. The National Assembly elected Yun Bo-seon president on August 13, 1960.

May 16, 1961

In the country’s first successful coup, South Korean army officer Park Chung-hee led thousands of troops into Seoul, seized power and deposed Yun.

Park occasionally imposed martial law to crack down on dissidents and political opponents.

October 26, 1979

Park was murdered in 1979. Choi Kyu-hah of Syngman’s corporatist, anti-communist Liberal Party initially rose to the top.

However, Choi was deposed in a military coup. Military rule initially applied to Seoul and other major cities, but was expanded nationwide in May 1980 by military leader Chun Doo-hwan.

Chun’s eight-year rule was marked by brutality and oppression.

This led to the Gwangju Uprising, a mass protest that broke out in the southern city of Gwangju on May 18, 1980. There were fears that hundreds of demonstrators had been killed in a crackdown by security forces.

In 1995, Chun was charged with mutiny and treason. He was subsequently sentenced to death but was pardoned in 1997. The Seoul High Court commuted its ruling in recognition of Chun’s role in rapid economic development.

Could Yoon be charged?

Growing public discontent with Yoon reached its peak when he declared martial law. He has since been condemned by members of his own party, the opposition party and the mayor of Seoul.

Six opposition parties, including the Democratic Party, filed an impeachment motion against Yoon on Wednesday. Yonhap News Agency reported that the vote on the motion is expected to take place on December 6 or 7.

Al Jazeera’s Kim reported that calls for Yoon’s impeachment are not new. People who did not vote for Yoon have organized several rallies in recent months. “They feel like they are being held back by the conservative government,” Kim said.

The mood that came from the outskirts has now intensified.

According to South Korea’s constitution, two-thirds of the members of the National Assembly must vote to impeach a sitting president.

The opposition parties, including the Democratic Party, have a combined total of 192 seats. They would need the support of at least eight members of Yoon’s People Power Party to pass the impeachment motion.

If the motion is approved, Yoon will be temporarily stripped of his authority as president until the Constitutional Court decides his fate.

Six of the court’s nine justices must vote to uphold the impeachment and remove Yoon.

A History of the Impeachment Trials in South Korea

Roh Moo-hyun: March 12, 2004

President Roh Moo-hyun of the social-liberal Yeollin Uri Party was impeached a year after his rise to the top office. He was charged with failing to maintain political neutrality. However, his removal from office was overturned by the Constitutional Court and he completed his five-year term.

Park Geun-hye: March 10, 2017

President Park Geun-hye, Park Chung-hee’s daughter, has been impeached for “acts that violate the constitution and laws” after months of political instability. The Constitutional Court voted unanimously to uphold her removal from office.

She was arrested in 2017 and sent to prison to serve a 20-year sentence on corruption charges. However, she was granted an amnesty in December 2021.