“If war is good for anything it is often good for fish,” alleges historian Carmel Finley (2011). She makes this claim in light of the dramatic decline in fisheries during WWI. The next world war also witnessed slowdowns in the international fish trade, then dominated by Japan, which reinforces Finley’s contention. But war and fish can’t be counterposed without making significant exceptions. Japan’s fisheries were foundational to its imperial ambitions, and by the 1930s, it had built up a “far-flung Fish Empire” (Tsutsui 2013, 32) that extended across Micronesia to Taiwan, Korea, and Manchuria, and its fishing fleets were found in all parts of the world, from the Arctic Circle to Antarctica. It was only after the attack on Pearl Harbor that the scale and scope of its fisheries contracted, as fishing vessels and crews were converted into naval ships and sailors. Moreover, wartime is not universally good for all fish: US catches of sardines and salmon intensified during WWII, and the same was true for sardines in Europe and Asia, given their value as food, fuel, and explosives. Sardines in particular were a crucial harvest for Imperial Japan, suggesting that not only is war not good for all fish but also some fish can be good for war.

The sardine fishery in the town of Changjŏn, Korea, is a case in point. It was a significant site of industrialization during the Japanese colonial period (1910–45), dominated by fishing and the processing of sardines (정어리; Sardinops sagax melanostictus). Drawn to the intersection of warm and cold ocean currents between the eastern coast of Korea and Japan, sardine migration routes brought huge catches to Changjŏn and thousands of migrant laborers to process them. Japanese pilots flew hydroplanes to locate the large dark shoals and signaled to the Korean trawlers who sailed out to scoop them up in large nets.

My father was born in Changjŏn, and when the total war effort began in 1941, he became a seven-year-old member of the imperial labor force. He recalls mammoth piles of fish dumped on the piers during the peak season and the mechanical presses used to extract their precious oils. He and his elementary school classmates would sort fish or transport wheels of pressed carcasses to a field where they would be sun-dried before being shipped off for further processing into dashi (soup stock) and fertilizer. The oil was used for various purposes, but most consequentially, after Pearl Harbor, for fuel and explosives, when the glycerin derived from sardine oil was converted into nitroglycerin.

In 1943, the sardines abruptly disappeared. My father recalls hearing that the Soviets had shot depth charges farther north to disrupt the fish migration routes, knowing that it would weaken the Japanese war effort. Just like that, the economy of Changjŏn collapsed. Long days of hunger and desperation followed, and as the Japanese Empire faced defeat, food rations diminished. My father and his friends would go up into the mountains to strip bark from pine trees, peeling off the soft inner layers to bring them home to their mothers who combined the bark with bean rations, making a filling—but barely palatable—meal.

Although I’ve been unable to verify the theory of the Soviet depth charges, the disappearance of the sardines has been well documented. In the southern part of the peninsula, over one million tons of sardines were caught in 1937, but they declined rapidly to zero by 1943. As in Changjŏn, residents in the southern port of Pusan associated the collapse of the sardines with the collapse of the empire. These small pelagic fish came to be known as ilmangch’i (일망치), or “Japan’s ruin.” A similar collapse of sardine stocks also occurred a few years later, on the other side of the Pacific, leading to the economic bust of the famous Cannery Row in Monterey, California. One marine biologist told me, “We won and the sardines lost.” He was referring to the US government’s wartime sanctioning of overfishing off the California coast, when 100 percent of the catch was used for military rations, despite the inevitable decimation of the sardine population. Meanwhile, in the Atlantic, Nazi Germany was also using the glycerin from sardines to manufacture nitroglycerine. In a celebrated battle, the British Navy dramatically blew up Nazi oil factories in the Lofoten Islands of Norway in 1941.

It might seem that no matter which side of the war they were connected to, sardines “lost” everywhere in the northern hemisphere, across the Atlantic and the Pacific. For colonized Koreans, calling sardines “Japan’s ruin” granted fish a measure of political agency and perhaps even sacrificial purpose—the sardines, in this scenario, were on the side of the winners, even as it meant economic collapse for Koreans as well. Canned for food, blasted by explosives, or turned into explosives––fish are entwined with human war in ways that defy the rudimentary heuristics of good/bad or winners/losers. Koreans’ characterization of sardines as ilmangch’i hints at the frangibility of human mastery at the interface of anthropogenic and evolutionary forces: Japan’s ruin is now all of ours.

Despite these intriguing historical connections, marine scientists I have spoken with do not include the industrialized militarization of fish in their models of what’s known as the “sardine-anchovy puzzle.” Instead, they describe “interdecadal regime shifts” attributed to changes in sea surface temperature that coincided with overfishing (Lindegren et al. 2013). Admittedly, much remains unknown in the study of fish lives, generational cycles, and marine ecosystems. The collapse of fish stocks and marine ecosystems due to overfishing alongside the cascading effects of industrial exploitation and toxicity constitute what Elsbeth Probyn calls the “complexity of fish-human-food entanglement” (2016, 19). This complexity needs also to attend to the militarization of fish and fisheries as part the longue durée of oceanic interconnections. From DDT-despoiled coastal waters off of California, to the North Korean “ghost ships,” a by-product of UN sanctions, to the intensification of maritime piracy in Somalia, ocean life is shot through with the material and cultural effluvia of war.