The Spanish for “to forget”, olvidar, has an interesting cousin in English: obliterate.
Both come from the same Latin root, obliterare, which means, “to cause to disappear; erase; blot out”, but was used in Latin slang to mean “to be forgotten.” You can see this in the o‑v-d of olvidar mapping to the o-(b)-l‑t of obliterate.
That which is forgotten is, in a sense, obliterated. As the Greeks reminded us: Chronos was a monster who ate his own children. All shall be forgotten!
Obliterare, in turn comes from the Latin root ob- (“against”) and littera (“letter”). Erasing is really just going against the letter itself, after all!