Mao era

In 1970, Lon Nol overthrew Sihanouk, and the latter fled to Beijing, where Pol Pot was also visiting. On the advice of the CCP, the Khmer Rouge changed its position, and in order to support Sihanouk, it established the National United Front of Kampuchea. In 1970 alone, the Chinese reportedly gave the United Front 400 tons of military aid. In April 1974, Sihanouk and Khmer Rouge leaders Ieng Sary and Khieu Samphan met with Mao in Beijing; Mao supported the policies which the Khmer Rouge proposed, but he did not want the Khmer Rouge to marginalize Sihanouk after they won the civil war and established a new Cambodia.

Rampart: A large earthen mound used to shield the inside of a fortified position from artillery fire and infantry assault. Occasionally ramparts might be constructed of other materials, such as sandbags.

South: Also called the Confederacy, the Confederate States of America, or (by Northerners) the Rebel states, the South incorporated the states that seceded from the United States of America to form their own nation. Southern states were: Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas, and Virginia.

Border States: The states of Maryland, Delaware, Kentucky, and Missouri. Although these states did not officially join the Confederacy, many of their citizens supported the South.

Parrott gun: A rifled artillery piece with a reinforcing band at the rear, or breech. Parrott guns were used by both the Army and the Navy, and ranged from 10-pounders to 300-pounders. They were named after their designer, Robert Parker Parrott.

Private: The lowest rank in the army.