What does 事実だけがでんと構えてる mean? What does mean? My breakdown of this sentence is, although I'm sure it's wrong: = the fact is = formally/officially = start something/ establish something So the sentence translated is: The fact of the matter is, something was established. Is this correct? I think there could be some nuance I'm missing though.

The () is an onomatopoeia for (the subject presenting itself) _grand_ or _big_.

here means or simply _to exist_.

The linked entries have relevant examples:

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> He had planted himself in the chair [ plunked himself down very firmly] and showed no sign of moving.
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> A big desk was placed ostentatiously [conspicuously] in the room.
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> He has the bearing [air] of an important person.

So the sentence in the question means literally _The fact alone is there firmly_. (I guess this is not a good translation, but makes sense in the context.)