B.E.20, or "B.E. 20," refers to a specific year in the Buddhist Era, which is used in several Southeast Asian countries. The Buddhist calendar is based on the life of the Buddha and is approximately 543 years ahead of the Gregorian calendar. Therefore, B.E. 20 corresponds to the year 1977 in the Gregorian calendar. In the context of historical events, B.E. 20 saw various developments in countries like Thailand and Cambodia. This period was marked by significant political changes and cultural events that shaped the region's history. Understanding B.E. 20 helps in studying the timeline of Buddhist cultural influence in Southeast Asia.