South Korean President Yoon faces impeachment: How did we get here?

South Korean President Yoon Suk Yeol is facing impeachment by parliament after a series of shocking moves that saw him briefly declare martial law in the country for the first time in nearly 50 years. 

South Korea's main opposition party, the Democratic Party, along with others, submitted the articles of impeachment on Wednesday, responding to what the DPK leader called an "unconstitutional and illegal declaration of martial law."

A motion for impeachment was reported to the National Assembly's plenary session Thursday in a parliamentary procedure that sets the stage for a full-house vote this week, according to local news.

The DPK reportedly plans to hold a plenary session to vote on the impeachment bill of the National Assembly on Saturday.

The party has a majority of control of the parliament, and along with members of other smaller opposition parties, it makes up 192 out of 300 seats. Thus, the coalition may only need eight outside votes to reach the two-thirds majority it would need to impeach the controversial leader.

If Yoon's impeachment is passed by parliament it moves to South Korea's Constitutional Court, which must then rule on whether to confirm or reject the impeachment.

The leader of Yoon's ruling People Power Party said Thursday that he plans to unite his party to block the motion to impeach.

In emails sent to NBC News, Yoon's office has maintained that his call for martial law was constitutional. 

However, the office confirmed that his chief of staff and all senior presidential secretaries had already tendered their resignation. Defense Minister Kim Yong-hyun also reportedly stepped down Thursday. 

Yoon plunged South Korea into six hours of turmoil from Tuesday night when he made a surprise declaration of martial law through a late-night TV address, mobilizing the country's military forces.

In an address on the country's YTN news channel, he said he was making the move "to protect the constitutional order," accusing opposition parties of sympathizing with North Korea and controlling parliament.

Following Yoon's announcement, a martial law proclamation stated that all political activities, including protests, strikes and the operations of the National Assembly, were prohibited.

All media was also declared under Martial Law Command, with the country's striking doctors ordered to return to work within 48 hours. 

Yoon's address was met with immediate nationwide backlash from lawmakers, citizens and unions. Meanwhile, defiant members of parliament raced to the National Assembly building for delegation. 

With 190 of its 300 members present, Parliament quickly passed a resolution demanding that Yoon lift the martial law as protests erupted outside the building. 

Amid the mounting pressure, early on Wednesday, Yoon made yet another national television appearance where he walked back the martial law declaration.

"I have accepted the decision made by the National Assembly to dissolve and lift the martial law," he said, though he urged the National Assembly to cease "repeated acts of impeachment, legislative manipulation and budgetary sabotage that paralyze the nation's functions."

South Korea's impeachment law is set out in its Constitution, which grants the National Assembly power to impeach the president if they violate the Constitution or other laws of official duty. 

If 200 members of parliament vote to impeach Yoon, the case will be escalated to the country's Constitutional Court and he will be suspended from exercising his powers until the results of a trial. 

According to the Constitutional Court Act of 1988, the Constitutional Court must make a final decision within 180 days. If Yoon chooses to leave office before the court's decision, the case is dismissed.

— NBC's Stella Kim and Jennifer Jett contributed to this report