should it be, "...the interest I had in these people..."?
That is what I would say... However, I would also use"who with their bare hands had uncovered history that had not been seen for nearly two thousand years."
what would you say? would you use "that?"
Delete "unexpectedly" since it's redundant with "surprised." [Have you ever been surprised expectedly?]
The sentence is wordy. Here's my suggestion:
I was surprised by my interest in these people who uncovered history with their bare hands and who saw what had not been seen for nearly two thousand years.
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