The Vietnam War took place within the region of Southeast Asia east of Thailand and south of China formerly known as Indochina, which is now comprised of the countries of Vietnam, Laos and Cambodia. Most of the fighting occurred within the country that was then known as South Vietnam, but the conflict spilled over into the neighboring countries of Laos and Cambodia to the east. Aerial bombing raids were also conducted over the area that was, at the time of the fighting, a separate country called North Vietnam.
The Vietnam War is also known as the Second Indochina War in order to distinguish it from the previous war waged by the indigenous population against the French when the region was a French colony. The war with France ended in a defeat for the French at the Battle of Dien Bien Phu in May of 1954 and the area formerly known as Indochina became the independent countries of Vietnam, Laos and Cambodia. Vietnam was partitioned at the 17th parallel by the accords of the 1954 Geneva Convention and became the two countries that were commonly referred to as North Vietnam and South Vietnam.
An organized communist insurgency against the then western-leaning government of South Vietnam brought the United States into the conflict. Troops from North Vietnam joined the fight in support of the insurgents, which led to increased U.S. military escalation and bombing raids over North Vietnam. North Vietnamese supply routes into the battle zones that crossed through Laos and Cambodia soon brought those regions into the conflict.