This is the 15067th most frequent Korean word.
발생했던
"That occurred" or "that happened."
In this sentence, '발생했던' is used as an adjective describing the noun '사건', referring to something that happened in the past and is being discussed in the current context.
지난 주에 발생했던 사건이 아직 해결되지 않았습니다.
The incident that occurred last week has not been resolved yet.
Here, '발생했던' is describing '상황', giving context to a specific time in the past when issues arose.
우리가 예측하지 못했던 문제가 발생했던 상황을 되짚어보았습니다.
We reviewed the situation where unexpected issues occurred.
In this instance, '발생했던' modifies '경제 문제', anchoring the timing of the issues to the past.