'was' followed by the past participle (verb-ed) is the past simple passive tense. The passive exists in all tenses in English. We use the verb 'to be' plus the past participle. 'To be' changes for each tense/ person, but the principle verb stays as the past participle. He was forced (by someone else/ circumstances) The sense of the passive is that the subject is not the doer of the action but rather the receiver. The opposite of passive is active. Here the subject is the doer of the action. Columbus discovered America = active. America was discovered in 1492 (by Columbus)= passive. It isn't always necessary to include by whom the action is/was done.

**verb +ed is not a formula Anyway, you have the passive voice here. He is forced. He was forced. He has been forced. Learn the "passive voice"!