The war's land fighting was concentrated in Europe, while its naval consequences extended across the oceans. German merchant seamen trying to return to Germany travelled aboard a Japanese freighter after starting their journey in America. Their interception at sea linked a European belligerent's personnel with shipping and routes far outside Europe. Calling the conflict a European war therefore understates its geographical reach at sea.
Notable Point · 1:26-2:11
Why a European war became global at sea
Land fighting was concentrated in Europe, but merchant voyages and naval interception carried the war across entire oceans.