The Cargo of the Lisbon Maru

On October 1, 1942, the American submarine USS *Grouper* sank the Japanese transport *Lisbon Maru*. The first line of the story was spare: a ship, a submarine, a sinking. The detail that changed its weight was learned later. The transport had been carrying 1,800 British prisoners of war from Hong Kong. Eight hundred died.

That later knowledge mattered. The *Lisbon Maru* was not simply a transport lost in an American submarine attack. It had carried men held prisoner after the fall of Hong Kong, and the sinking killed hundreds of them. The known total—800 dead—was a large part of the ship’s 1,800 prisoners. The figures made the human cost plain, even where the brief account supplied no further detail about the sinking or the prisoners’ circumstances.

The date’s record placed the sinking among other events of October 1, including an Australian commando raid on Mubo in New Guinea and the end of the Battle of Rzhev, Summer 1942. Those entries had their own military measures: Japanese killed in the raid, or a Soviet operational failure at Rzhev. The *Lisbon Maru* entry was different in kind. Its most important fact was not a tactical result but what the ship had been carrying—and how many of those prisoners died.

The account did not give a position for the sinking, describe the attack, or say what happened to the remaining prisoners. Those absences were worth keeping. They did not make the central fact uncertain: USS *Grouper* sank the transport, and 800 of the 1,800 British prisoners aboard died. The later discovery of the cargo turned a short naval report into a record of mass death among prisoners of war. The ship’s name remained; the manifest, once known, changed what the name meant.