I think it began as intelligence gathering by the dems on the opposition (Trump). They knew he was a real threat of getting elected and they needed Hillary to gain the office to keep all the evidence of their nefarious activities smothered until time could erase all evidence.
By dems, I mean the Obama administration, the Hillary cabal, the deep state, etc.
When Trump won, the dem players switched to using their powers to hamper his success and to unseat him. All the while preventing any of their previous criminal actions from being made public.
Plain and simple: Treason.
Except it seems to have started LONG before Trump announced, or even was a serious front-runner.