25 June - North Korean People's Army (NKPA), with 60,000 troops and 100 Russian tanks, crosses 38th Parallel to invade South Korea.

25 June - United Nations Security Council calls for end of aggression and withdrawal of NKPA troops.

27 June - UN, adopting a U.S. resolution, proclaims NKPA attack a breach of world peace. Asks member nations to assist the Republic of Korea (ROK) in repelling invasion.

27 June - President Harry S. Truman orders U.S. air-sea units to support ROK and for U.S. Seventh Fleet to neutralize Formosan Strait.

28 June - NKPA captures Seoul, South Korean capital.

29 June - President Truman orders naval blockade of Korean coast and authorizes Far East Commander, Gen Douglas A. MacArthur, USA to send U.S. ground troops into Korea.

30 June - President Truman receives Congressional authorization to order into active service any or all reserve components of Armed Forces for a period of 21 months.

2 July - The Chief of Naval Operations (CNO) directs that Marine reinforced regiment with supporting air be prepared for assignment to Far East.

2 July - The Commander in Chief, Far East (CinCFE) requests a Marine Regimental Combat Team (RCT)-air unit for Far East. This was inception of 1st Provisional Marine Brigade (1st ProvMarBrig), formed less than a week later.

3 July - Inchon captured by North Koreans.

5 July -4 August - United Nations Command (UNC) fights series of delaying actions in Korea.

7 July - UN Security Council authorizes formation of a United Nations Command as counter force against NKPA aggression.

7 July - 1st ProvMarBrig activated at Camp Pendleton, under BGen Edward A. Craig. Basic elements of 6,534-man Brigade are 5th Marines and Marine Aircraft Group 33 (MAG-33).

8 July - Gen MacArthur named Commander, UNC.

10 July - The Commander in Chief, United Nations Command (CinCUNC) asks Joint Chiefs of Staff (JCS) to authorize expansion of Marine Brigade to full war-strength division.

12-14 July - 1st ProvMarBrig embarks for Korean theater.

12 July - LtGen Walton H. Walker named CG, Eighth U.S. Army in Korea (EUSAK).

19 July - CinCUNC makes 2d request for Marine division.

19 July - President Truman authorizes Defense Dept to call up reserve units and individuals.

19 July - The Commandant of the Marine Corps (CMC), Gen Clifton B. Cates, alerts Marine Corps organized reserve units for call to active duty following Presidential announcement.

20 July - CMC orders to duty Organized Marine Corps ground reserve units, consisting of 22 units and 4,830 personnel. Partial call up for 6,000 air reservists in 30 Marine Fighter (VMF) Squadrons and 12 Marine Ground Control Intercept (MGCI) Squadrons.

20 July - Taejon, temporary Republic of Korea (ROK) capital, captured.

21 July - CinCUNC makes 3d request for Marine division.

25 July - UNC defense at Pusan deteriorates. CinCUNC orders 1st MarProvBrig directly to Korea.

25 July - JCS directs Marine Corps to build 1st MarDiv to war-strength.

31 July - Masan and Chinju fall to enemy.

2-3 August - 1st ProvMarBrig arrives Pusan. Moves to bivouac area near Masan.

3 August - First Marine air strike launched by VMF-214.

4 August - Pusan Perimeter established by UNC in southeastern end of Korea.

4 August - First evacuation of casualties from Pusan by Marine Observation Squadron Six (VMO-6) helicopters.

6 August - First air mission flown by VMF-323.

6-8 August - CinCUNC confers with U.S. military-diplomatic officials about proposed Inchon amphibious landing.

7-13 August - Marine Brigade engaged in first combat operations at Chinju.

10 August - First Marine helicopter rescue made by VMO-6 to recover downed pilot.

10-24 August - 1stMarDiv units embark for Korea.

16 August - EUSAK X Corps activated for coming Inchon-Seoul operation. Principal elements are 1stMarDiv and Army 7thInfDiv.

17 August - Marine Brigade opens battle for Obong-ni ("No Name") Ridge, leading way to destruction of enemy bridgehead at Naktong and first UNC victory in Korea.

17 August - 7th Marines activated at Camp Pendleton and on 1 September embarks for Far East, arriving 21 September.

1-5 September - NKPA launches all-out offensive to break UNC perimeter defense at Pusan. In Second Naktong Battle, Brigade contains enemy at Yongsan.

13 September - 1st ProvMarBrig deactivated and absorbed by 1st Marine Division (1stMarDiv) for Inchon operation.

15 September - D-Day, Inchon amphibious assault, spearheaded by 1stMarDiv.

17 September - 1stMarDiv (5th Marines) recaptures Kimpo Airfield.

19-25 September - Enemy resistance at Pusan begins to collapse. NKPA troops in retreat north from Pusan.

27 September - 1stMarDiv recaptures Seoul. ROK Capital officially liberated 29 September.

30 September - Communist China Foreign Minister Chou En-Lai warns: "The Chinese people will not supinely tolerate seeing their neighbors being savagely invaded by the imperialists."

30 September - 1 October - ROK 3d Div crosses 38th Parallel in pursuit of retreating NKPA.

7 October - UN General Assembly authorizes UNC forces to cross 38th Parallel to defeat NKPA.

10 October - Wonsan, east coast port at 39th Parallel, captured by ROK troops.

10 October - Chinese repeat warning of intervention in Korean conflict.

16 October - First Chinese Communist troops secretly enter Korea from Manchuria.

19 October - Pyongyang, North Korean Capital at 39th Parallel, captured by EUSAK.

26 October - Chinese troops attack ROK units at Yalu River and points south of Sino-Korean border.

26 October - 1stMarDiv lands at Wonsan, establishes security for port, and drives north.

1 November - UNC forward elements reach positions along Yalu. First Russian-built MiG appears along Yalu to attack U.S. aircraft.

2 November - Strong Chinese and NKPA forces attack EUSAK at Unsan, causing withdrawal across Chongchon River. First identification of Chinese Communist Forces (CCF) in Korea.

6 November - Initial Marine encounter with CCF. 7th Marines units defeat major elements of 124th CCF Division.

3-7 November - Gen MacArthur warns JCS that movement of CCF across Yalu threatens UNC position.

15 November - Marine units reach Chosin Reservoir area in X Corps drive north.

24 November - Gen MacArthur announces "win the war" offensive. EUSAK begins advance toward Yalu.

26-27 November - CCF, 200,000 strong, attack EUSAK troops forcing withdrawal. 1stMarDiv isolated at Yudam-ni, west of Chosin. Main Supply Route (MSR) cut.

28 November - 3 December -1stMarDiv turns back CCF attacks. Prepares to move south. Regroups at Hagaru-ri for drive to Hungnam.

4 December - Pyongyang recaptured by enemy.

5-7 December - 1stMarDiv evacuates wounded by air and fights through to Koto-ri.

6 December - Innovation of using airborne Tactical Air Direction Center (TADC) as tactical Command Post (CP) to control air support.

10 December - First Marine jet squadron to fly in combat, VMF-311, begins operations.

11 December - 1stMarDiv completes fighting breakout from Chosin entrapment. Begins march to join rest of X Corps at Hungman.

15 December - 1stMarDiv deployed from Hungnam to Pusan.

15 December - UNC establishes new defensive line at 38th Parallel.

18 December - 27 January - 1stMarDiv routes enemy guerrilla forces in Masan-Pohang-Sondong-Andong area.

23 December - EUSAK Commanding General Walton H. Walker, USA, killed in jeep accident. Gen Matthew B. Ridgway, USA, named to succeed him.

24 December - Hungman evacuation completed by X Corps.

29 December - Large enemy buildup reported north of 38th Parallel, preparing for new attack.


31 December - 1 January - Enemy launches all-out offensive against UNC across 38th Parallel, pushing EUSAK back 10-12 miles.

4 January - Seoul recaptured by Communists.

7-15 January - Enemy offensive halted. UNC sets up new defense line along Pyongtaek-Wonju axis, at 37th Parallel.

25 January - UNC reassumes offensive. Operation Thunderbolt launched by I and IX Corps to regain territory south of Han River.

January - February - 1stMarDiv continues anti guerrilla operations in Masan area.

7 February - Communists forced north of Han River. UNC retakes Inchon peninsula.

mid-February - 1stMarDiv reassigned from X to IX Corps.

21 February - Operation Killer, a general limited objective advance by U.S. IX and X Corps, ordered by Gen Ridgway. 1stMarDiv reenters frontline's for operation.

7 March - Operation Ripper begins in central and eastern zones, with advance across Han River by IX and X Corps.

14 March - Seoul retaken by U.S. Eighth Army for second time.

27-31 March - 1stMarDiv occupies 28,000-meter sector north of Hongchon. UNC elements reach 38th Parallel.

1-21 April - 1stMarDiv in general advances north to the Hwachon Reservoir.

8 April - Operation Ripper clears enemy troops from South Korea east of Imjin River.

11 April - President Truman relieves Gen MacArthur as CinCUNC, replacing him with Gen Ridgway, CG, EUSAK. LtGen James A. Van Fleet named Commander, EUSAK.

15 April - UNC establishes defensive line along 38th Parallel, or KANSAS Line. Enemy heavily emplaced in Chorwon-Kumhwa-Pyonggang ("The Iron Triangle") assembly area.

22 April - 18 July - CCF launches all-out "Spring Offensive."

23-27 April - 1stMarDiv halts CCF left flank breakthrough of IX Corps, establishes defense line in Chunchon vicinity.

30 April - UNC completes withdrawal to new defense line north of Seoul. Intelligence reports indicate that CCF plans renewed attack.

1 May - 1stMarDiv reassigned to X Corps.

9 May - 1st MAW squadrons participate in Fifth Air Force (FAF) 300-plane strike on Sinuiju, near Yalu. Biggest raid of war to date.

16 May - Second phase of enemy offensive begins. CCF drives south from Iron Triangle area, making penetrations 15-20 miles deep along the front.

20 May - FAF launches Operation Strangle, a massive all-out interdiction effort.

21 May - UNC launches counter offensive, pushes enemy north of 38th Parallel again. 1st MarDiv drives toward Yanggu at eastern end of Hwachon Reservoir.

30 May - Eighth Army back on Kansas Line again.

1-16 June - 1stMarDiv advances northeast from Hwachon Reservoir to Punchbowl. Claws out daily gains of 1,000-2,000 meters, reaching objective despite heavy NKPA fire.

mid-June - UNC forces consolidate positions at 38th Parallel. UNC front approximately the same line as when Communist spring offensive began.

23 June - UN Soviet delegate, Jacob Malik, proposes cease fire discussions.

30 June - UN notifies enemy of its readiness to discuss an armistice.

10 July - Truce talks begin at Kaesong and fighting dies down along front. UN delegation led by U.S. Vice Admiral C. Turner Joy, USN. Communists represented by LtGen Nam Il, NKPA.

26 July - Negotiators at Kaesong agree on preliminary agenda.

5 August - UNC suspends truce talks because of armed enemy troops in neutral area. Cease-fire talks resumed 10 August.

22 August - Communists halt cease-fire talks, charge UN aircraft has violated neutrality zone.

31 August - In final UNC offensive action of war, 1stMarDiv opens assault at Punchbowl. UN launches limited attacks to straighten line.

5 September - 1stMarDiv gains initial objectives in Punchbowl area, new ridgeline to become part of Line Minnesota, EUSAK defensive line. Heavy attacks by IX Corps at Heartbreak and Bloody Ridge.

13 September - Marine Helicopter Transport Squadron -161 (HMR-161) effects first Marine mass helicopter combat resupply maneuver, in Operation Windmill I.

18 September - Marines advance to Soyang River, north of Punchbowl.

21 September - Operation Summit, first helicopter deployment of a combat unit, lands 224 fully-equipped troops and 17,772 lbs of cargo in Punchbowl area.

25 October - Following two weeks of discussion between liaison officers, truce talks resumed at new site, Panmunjom.

28 October - Cease-fire line agreed upon as present line of contact.

11 November - HMR-161 conducts first frontline relief of a Marine battalion, in Operation Switch.

12 November - Gen Ridgway, CinCUNC, orders EUSAK Commander, Gen Van Fleet to cease offensive operations and begin active defense of UN front.

November-December - General stalemate along Korean battlefront during truce discussions.

18 December - Prisoner of war (POW) lists exchanged by UN and Communists.


2 January - UNC proposes principle of "voluntary repatriation" in POW exchange.

3 January - UNC proposal violently rejected by Communists.

January-April - Disorders in UNC prison camps as screening of prisoners begins.

22 February - Communist Korean Foreign Affairs Minister charges America with renewed bacteriological warfare attacks in North Korea. Chinese Communist Foreign Minister Chou En-Lai, issues similar statement on 8 March, alleging U.S. flyers participate in "germ warfare."

17 March - 1stMarDiv reassigned from X Corps eastern-Korea position to I Corps far western end of EUSAK line. Takes over approximately 3 miles of Line Jamestown on 24 March.

28 April - Adm Joy presents UN "final offer," insists on voluntary repatriation principle.

7-11 May - Rioting prisoners at Koje-do camp seize Gen Dodd and hold him hostage, until order restored.

12 May - Gen Mark W. Clark, USA, succeeds Gen Ridgway as CinCUNC, upon latter's departure to assume NATO command from Gen Eisenhower.

22 May - MajGen William K. Harrison, USA, succeeds Adm Joy as chief of UN delegation at Panmunjom.

June-October - General stalemate along battlefront while truce talks deadlocked on POW repatriation question. Sharp limited objective attacks made by enemy against UNC defensive line.

9-16 August - First major Marine ground action in western Korea, Battle of Bunker Hill (1st Marines).

19-20 August - HMR-161 Operation Ripple introduces tactical innovation of transporting 4.5-inch rocket battery weapons and personnel to new firing position.

29 August - Largest one-day FAF air assault of entire war, "All United Nations Air Effort" sends 1,403 sorties against North Korean Capital, Pyongyang.

22-26 September - First resupply of MLR regiment by helicopter in Operation Haylight.

8 October - UNC adjourns armistice talks "indefinitely." There is complete deadlock on POW question.

26-28 October - Battle of the Hook (7th Marines).

4 November - Dwight D. Eisenhower elected President.

17 November - India introduces compromise truce plan at United Nations.

2 December - President-elect Eisenhower begins three-day tour of Korea.

3 December - UN General Assembly adopts compromise Indian resolution by 54 to 5 vote.


January-February - Winter lull in fighting. Cease-fire talks remain suspended.

2 February - President Dwight D. Eisenhower, in State of Union message, ends "neutralization" of Formosa Strait.

11 February - Gen Maxwell D. Taylor assumes EUSAK command from Gen Van Fleet.

22 February - UNC proposes exchange of sick and wounded POWs' as preliminary step in full exchange of prisoners.

5 March - Premier Joseph Stalin of Russia dies. Georgi Malenkow named to succeed him.

26-30 March - 1stMarDiv combat outposts Vegas-Reno-Carson (5th Marines) under heavy attack.

28 March - Communists accept UN proposal to discuss exchange of sick and wounded POWs.

30 March - Chou En-Lai indicates Communists will accept Indian UN compromise proposal. Truce talks to be resumed.

12 April - 1st MAW flies first night Close Air Support (CAS) missions, using intersecting searchlight beams to mark enemy targets.

20-26 April - Exchange of sick and wounded POWs, "Operation Little Switch," takes place at Panmunjom, under direction of Munsan-ni Provisional Command.

26 April - Truce talks resumed at Panmunjom.

5 May - 1stMarDiv relieved by U.S. 25thInfDiv; 1st Division assigned mission of I Corps Reserve.

7 May - Communists accept UN proposal that prisoners unwilling to be repatriated be kept in neutral custody within Korea, rather than be removed elsewhere to a neutral nation.

28-30 May - Savage fighting while truce details worked out by negotiators. CCF launches regimental-strength attack against I Corps sector. Heavy action in Nevada Cities and Hook area outposts. Marine tanks and artillery in support of defending 25thInfDiv line units.

6 June - ROK National Assembly demands freedom for anti-Communist North Koreans held in South Korean POW camps. Civilian demonstrations break out in various EUSAK and I Corps localities.

8 June - Agreement reached on POW question. POW nonrepatriates to be turned over to five member neutral commission to decide disposition of POW cases. Pres Rhee declares armistice terms unacceptable to South Korea.

9 June - ROK National Assembly unanimously rejects truce terms.

10-17 June - Communists launch heaviest offensive in two years against ROK II Corps sector in Kumsong area. Heavy penetrations, with ROK II Corps pushed 4000 yards south to new MLR.

18 June - Breakout of 25,000 North Korean anti-Communist prisoners from South Korean POW camps, assisted by ROK guards. Release ordered by Pres Rhee as protest against proposed armistice.

18-20 June - Communists accuse UNC of complicity in freeing prisoners; truce talks suspended.

23-25 June - Pres Rhee continues opposition to truce terms. Walter Robinson, U.S. Asst. Sec. of State for Far East, and Gen Mark Clark, start confidential talks with Rhee.

7-8 July - Combat Outposts (COPs) Berlin-East Berlin (7th Marines right regimental sector) under attack during Marine relief of 25thInfDiv.

8 July - 1stMarDiv assumes operational control of its former MLR section, relieving 25thInfDiv.

8 July - Communists agree to resume armistice negotiations; talks reconvened 10 July.

11 July - Robertson announces that Pres Rhee will no longer oppose truce terms.

11 July - Maj John F. Bolt, VMF-115, becomes first Marine jet ace with kills of his fifth and sixth MIGs.

13-20 July - CCF launches even larger offensive than June attack along central Korean front. IX and ROK II Corps MLR reestablished south of Kumsong River.

19 July - Negotiators at Panmunjom reach agreement on truce.

19 July - Marine outposts Berlin-East Berlin overrun; I Corps decrees positions should not be retaken.

24-27 July - Heavy enemy attack in Berlin Complex ("Boulder City") area held by 7th and 1st Marines.

27 July - Ceasefire agreement signed at Panmunjom at 1000. Fighting ends. Armistice effective at 2200.

5 August - 6 September - Final exchange of prisoners in Operation Big Switch, at Panmunjom.


Extracted, with minor revisions, from Lieutenant Colonel Pat Meid, USMCR, and Major James
M. Yingling, USMC, Operations in West Korea, Vol V. of U.S. Marine Operations in Korea,
1950-1953 (Washington: Government Printing Office, 1972).

Marine Corps University