Question: when did north vietnam declare war on south vietnam

title: Vietnam War
text: Estimates of the number of casualties vary , with one source suggesting up to 3.8 million violent war deaths in Vietnam for the period 1955 to 2002 . Between 195,000 and 430,000 South Vietnamese civilians died in the war . Extrapolating from a 1969 US intelligence report , Guenter Lewy estimated 65,000 North Vietnamese civilians died in the war . Estimates of civilian deaths caused by American bombing of North Vietnam in Operation Rolling Thunder range from 52,000 to 182,000 . The military forces of South Vietnam suffered an estimated 254,256 killed between 1960 and 1974 and additional deaths from 1954 to 1959 and in 1975 . The official US Department of Defense figure was 950,765 communist forces killed in Vietnam from 1965 to 1974 . Defense Department officials believed that these body count figures need to be deflated by 30 percent . In addition , Guenter Lewy assumes that one - third of the reported `` enemy '' killed may have been civilians , concluding that the actual number of deaths of communist military forces was probably closer to 444,000 . It was difficult to distinguish between civilians and military personnel on the Viet Cong side as many persons were part - time guerrillas or impressed laborers who did not wear uniforms . A detailed demographic study calculated 791,000 -- 1,141,000 war - related deaths for all of Vietnam . According to figures released by the Vietnamese government in 1995 , there were 1,100,000 North Vietnamese Army and Viet Cong military personnel deaths during the Vietnam War ( including the missing ) . The Vietnamese government released its estimate of war deaths for the more lengthy period of 1955 to 1975 . According to the Vietnamese , Communist battle deaths totaled 1.1 million and civilian deaths of Vietnamese totaled 2.0 million . These estimates probably include battle deaths of Vietnamese soldiers in Laos and Cambodia , but do not include deaths of South Vietnamese and allied soldiers which would add nearly 300,000 for a grand total of 3.4 million military and civilian dead .