What is the past tense of let go?

Answer 1

let us gone

If "let go" means "release" me or "drop it", it's "let go". (Only "let" is a Past Tense, as "go" is a short infinitive, therefore - it stays the same).

Answer 2

The past tense of "let go" is "let go" as it remains the same in both present and past tense.

Answer 3

Gone

Answer 4

I don’t know