This is the 909th most frequent Turkish word.
olmuştu
"Olmuştu" means "had happened" or "had been" in English, indicating past perfect tense.
In this sentence, 'olmuştu' is used to refer to an event that had occurred in the past before another past referencing event.
Dün hava çok kötü olmuştu.
Yesterday, the weather had turned very bad.
In this sentence, 'olmuştu' expresses that a resolution to the problem had been achieved prior to another past event or reference.
Bu problem zaten önceden çözülmüş olmuştu.
This problem had already been solved earlier.
Here, 'olmuştu' is part of the past perfect tense, indicating actions completed before the past action of 'the event started'.