'Oblivion' may trace to Latin 'levis' (smooth) — forgetting as the mind going blank and featureless.
The state of being unaware or unconscious of what is happening; the state of being completely forgotten.
From Latin 'oblīviō' (forgetfulness, the act of forgetting), from the verb 'oblīvīscī' (to forget), from 'ob-' (over, against) + a root related to 'lēvis' (smooth) — PIE *h₁leh₁- (smooth, gliding) — the metaphor being that the mind is wiped smooth, its stored impressions erased. Another analysis connects 'oblīvīscī' to 'līvor' (bruise, black-and-blue mark) suggesting memory wiped away like a stain, but the 'smooth' etymology has stronger scholarly support. The Romans formalized oblivion as a political instrument: the 'Lex Oblivionis' (Law of Forgetting) and similar 'Acts
The 'Act of Oblivion' (1660) pardoned participants in the English Civil War by officially 'forgetting' their offenses.