noun
occupation period
Refers specifically to the period after WWII when Japan was under Allied occupation (1945–1952). Used in historical and political contexts.
被占領期の日本では、多くの改革が行われた。
During the occupation period, many reforms were carried out in Japan.
この法律は被占領期に制定された。
This law was enacted during the occupation period.
占領下 means 'under occupation' and is a broader term that can refer to any occupation, while 被占領期 specifically denotes the historical period of occupation.
Compound of 被 (hi, 'subjected to'), 占領 (senryō, 'occupation'), and 期 (ki, 'period').