Naval Fieldpost No. 5 aboard the Kamakura Maru serves Yap until stationary naval post offices open from 10 October 1915.

What happened

In the first year of occupation, mail on Yap was handled by a naval field post office aboard a supply ship, the Kamakura Maru; permanent naval post offices on the islands followed. The details come from a postal-history exhibit and the German certificate attached to one card.