'True' originally meant 'faithful' — from PIE *deru- (firm as a tree). Loyalty before factual accuracy.
In accordance with fact or reality; genuine, authentic; loyal, faithful.
From Old English 'trēowe' (faithful, trustworthy, honest), from Proto-Germanic *triwwiz, from PIE *drewh₂- meaning 'firm, solid, steadfast' — literally 'like a tree.' The same PIE root produced 'tree,' 'trust,' 'truce,' and 'troth,' as well as the second element of 'betroth.' The original meaning was not 'factually correct' but 'faithful, loyal, steadfast' — truth was conceived as a quality of persons
'True' and 'tree' are etymological siblings — both descend from PIE *drewh₂- meaning 'firm, solid, steadfast,' with the tree being the archetypal firm, upright thing. To be true was originally to be as solid and steadfast as a tree. The phrase 'plight one's troth' (pledge one's truth/loyalty) preserves the original sense of personal fidelity.