Quick answer

When did Shanks lose his arm?

The answer

Shanks lost his left arm saving young Luffy from a Sea King in Foosha Village.

Ch. 1.1, p. 9

Verified through chapter 1.1Updated

What the manga shows

3 facts
  1. The Sea King bites down hard on Shanks' left arm during the rescue.

    Ch. 1.1, p. 15

  2. Shanks states the arm loss is a small price and expresses relief that Luffy is safe.

    Ch. 1, p. 43

  3. Shanks' left arm has been completely bitten off at the shoulder by the sea monster.

    Ch. 1, p. 47

Change log

2 chapters
  1. Chapter 1.1Added 1 fact; updated the answer
  2. Chapter 1Added 2 facts

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