This study analyzes the impact of the ‘Great Proletarian Cultural Revolution’ on Sino-Vietnamese relations in the context of the 1968 Mậu Thân Offensive, thereby illuminating an underexplored dimension of the Cold War history in East Asia. Using a historical–policy analytical approach and systematically drawing on archival materials, diplomatic documents, and recent Chinese scholarship, the article demonstrates that internal political upheavals resulting from the Great Proletarian Cultural Revolution directly reduced China’s military and economic aid to Vietnam, while simultaneously restructuring the China-Vietnam-Soviet Union triangle toward heightened ideological tensions. At the same time, the study shows that the 1968 Mậu Thân Offensive was not only a turning point in the Vietnam War but also exerted a reverse influence on Beijing’s foreign policy, indirectly facilitating Sino-American rapprochement from the late 1960s. By situating these two major historical events of Vietnam and China within a unified analytical framework, the article offers a novel interpretation of the role of China’s domestic politics in the Vietnam War and the shifting balance of power in the Cold War in East Asia.
Le Dinh Trong (Fri,) studied this question.