Complex sentence: The Diệm regime (1954--63) had staged elections before in South Vietnam, but saw their utility from a traditional point of view, e.g., as an "national holiday" event for the ruling party to muster its popular support and mobilize the population.
Split into simpler sentences: The Diệm regime (1954--63) had staged elections before in South Vietnam, but saw their utility from a traditional point of view. As practiced in similarly situated countries, elections were viewed as an "national holiday" event for the ruling party to muster its popular support and mobilize the population.