HistoryData
Historical ConflictMasan

Battle of Masan

The Battle of Masan secured the southern flank of the Pusan Perimeter, preventing North Korean forces from reaching the critical port of Pusan.

Duration & Scope

1950 ongoing

< 1 year

Key Facts

Duration
August 5 – September 19, 1950
Length
~6 weeks
KPA divisions engaged
2 (6th and 7th Divisions)
Primary US unit
25th Infantry Division
Part of
Battle of Pusan Perimeter

Strategic Narrative Overview

The KPA 6th and 7th Divisions launched repeated attacks over six weeks against the 25th Division's three regiments. An initial UN counteroffensive from Masan failed to halt KPA advances. The 35th Infantry Regiment successfully repelled KPA forces at the Battle of Nam River, earning distinction. The 24th Infantry Regiment performed poorly at Blue Mountain and Haman, compelling the 25th Division to commit reserves to stabilize the line against KPA breakthroughs.

01 / The Origins

In the summer of 1950, North Korean People's Army (KPA) forces swept rapidly southward into South Korea following the June 1950 invasion, pushing UN and South Korean troops into a shrinking defensive pocket around the port of Pusan. The US 25th Infantry Division was assigned to hold the extreme southern flank of this perimeter around the city of Masan, guarding approaches through the Naktong River valley and the surrounding hills.

03 / The Outcome

By September 19, 1950, UN forces had repelled all KPA attacks in the Masan sector, ending the battle in a UN victory. The successful defense of this southern flank helped preserve the Pusan Perimeter as a whole, enabling the subsequent UN breakout following the Inchon landings in mid-September 1950. The KPA divisions were exhausted and unable to achieve their objective of capturing Pusan.

Belligerents & Mobilization Analysis

Side A

1 belligerent

Korean People's Army (KPA)

Side B

1 belligerent

United Nations Command / United States Army
Outcome
UN victory; KPA 6th and 7th Divisions repelled; southern flank of Pusan Perimeter held

Kinetic Engagement Axis

Major engagements timeline (1950–present)Timeline of major military engagements plotted chronologically.1950present1950Battle of Nam Ri…Side B1950Battle of Blue M…Allied1950Battle of HamanAllied

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of Masan, South KoreaMap of Masan, South KoreaMasan, South Korea