This is the 18439th most frequent Russian word.
эпохи
"Epochs" or "eras."
In this sentence, the word 'эпохе' (which is the dative case form of 'эпоха', meaning 'era') is used to specify a historical period being discussed.
Эта книга рассказывает об эпохе Возрождения.
This book tells about the era of the Renaissance.
Here, 'эпохами' (instrumental case plural of 'эпоха') indicates various historical periods of art.
Я интересуюсь разными эпохами в истории искусства.
I am interested in different eras in art history.
The word 'эпохе' in the dative case singular, used after 'одной' to describe a singular historical period transitioning to another.