Dec 3, 2024 – Yoon Suk‑yeol announces a nationwide martial‑law decree, accusing “anti‑state forces” of colluding with North Korean communists and orders troops to descend on the National Assembly; lawmakers break the military blockade, seize a rifle, and unanimously lift the decree after six hours, ending the brief emergency order[2][4].

Dec 14, 2024 – The National Assembly votes to impeach Yoon, marking a swift constitutional response to the failed coup attempt[1].

Jan 3, 2025 – After two‑and‑a‑half weeks confined in the presidential residence, Yoon is arrested by authorities, initiating criminal proceedings against the former president[1].

Apr 2025 – The Constitutional Court formally removes Yoon from office, cementing his ouster following the impeachment vote[5].

Jul 2025 – Yoon remains in custody as multiple criminal cases related to the martial‑law episode proceed, including charges of obstruction and rebellion[5].

Jan 16, 2026 – A Seoul court hands Yoon a five‑year prison term for defying detainment and fabricating the martial‑law proclamation, the first verdict among eight criminal cases tied to the 2024 crisis[6].

Feb 19, 2026 – The Seoul Central District Court convicts Yoon of insurrection and sentences him to life imprisonment, noting his intent to paralyze the National Assembly by deploying troops; co‑defendants including former Defense Minister Kim Yong‑hyun (30 years) and former police chiefs receive lengthy terms[9][10].

Feb 19, 2026 – Judge Jee Kui‑youn explains that Yoon’s decree aimed to block legislative work, describing the act as a “riot staged with the military” and emphasizing the legal definition of insurrection based on intent to subvert a constitutional body[4][11].

Feb 22, 2026 – Gi‑Wook Shin, director of Stanford’s Korea program, tells the BBC that the Yoon case “offers a rare example of democratic resilience,” highlighting the trial as a test of South Korea’s safeguards against authoritarianism[1].

Feb 24, 2026 – Yoon’s lawyers file an appeal challenging the life‑prison verdict, arguing the indictment is politically motivated and pledging to document procedural flaws for the historical record[8].

Historical context (1980s‑1990s) – The 2024 martial‑law attempt is the first since former dictator Chun Doo‑hwan’s 1980 coup, whose 1996 death sentence was later reduced to life and pardoned in 1997; South Korea has maintained a de facto moratorium on executions since 1997, influencing the court’s decision to impose life rather than death[2][5].