The battle for Outpost Vegas took place during the Korean War between the armed forces of the United Nations Command (UN) and China from 26 to 30 March 1953, four months before the end of the Korean War. Vegas was one of three outposts called the Nevada Cities north of the Main Line of Resistance (MLR), the United Nations defensive line which stretched roughly around the latitude 38th Parallel. Vegas, and the outposts it supported, Reno and Carson, were manned by elements of the 1st Marine Division. On 26 March 1953 the Chinese People's Volunteer Army (PVA) launched an attack on the Nevada Cities, including Vegas, in an attempt to better the position of China and North Korea in the Panmunjon peace talks which were occurring at the time, and to gain more territory for North Korea when its borders would be solidified. The battle raged for five days until PVA forces halted their advance after capturing one outpost north of the MLR on 30 March, but were repelled from Vegas. The battle for Outpost Vegas and the surrounding outposts are considered the bloodiest fighting to date in western Korea during the Korean War. It is estimated that there were over 1,000 American casualties and twice that number of Chinese during the Battle for Outpost Vegas. The battle is also known for the involvement of Sergeant Reckless, a horse in a USMC recoilless rifle platoon who transported ammunition and the wounded during the U.S. defense of outpost Vegas.

The 1st Marine Division is a Marine division of the United States Marine Corps headquartered at Marine Corps Base Camp Pendleton, California. It is the ground combat element of the I Marine Expeditionary Force.