Where does Poke come from?
Poke comes from Hawaii. Its name is the Hawaiian word for 'to slice' or 'cut crosswise into pieces', and it began as fresh fish cut up and eaten raw with sea salt, seaweed and roasted kukui nut, long before the poke bowl went around the world.
Raw fish, salt and seaweed
In old Hawaii most protein came from the sea, and fresh raw fish was a delicacy. Pieces cut from the catch were eaten as a snack, seasoned with sea salt, limu (edible seaweed) and ʻinamona, roasted kukui nut with salt. Most fish came from fishponds, reefs and shallow water; under the kapu system, deep-sea fishing beyond the reef was reserved for chiefs. William Ellis recorded that Europeans learned the Hawaiian habit of biting into a small raw fish on the reef.
New ingredients, new name
Captain Cook brought onion seeds in 1778, and onions became a popular addition. From the mid-1800s immigrants from China and Japan came to work on the plantations, bringing soy sauce and sesame oil, and Japanese cooks added soy sauce to cubes of ʻahi tuna. The dish's name may be fairly new: the food historian Rachel Laudan suggests 'poke' may have meant this dish only from the 1960s. Its present form became popular in the 1970s, when it also appeared in supermarkets.
Why people think of Japan
Poke looks like Japanese sashimi, and today it is often dressed with soy sauce and served over rice. Japanese influence on Hawaii's fishing is real: in the 1920s and 1930s almost all the fishing boats in Hawaiian waters belonged to Japanese fishermen, and many local fish are still known by both Hawaiian and Japanese names. But cutting up raw fish and seasoning it with salt, seaweed and kukui nut is a Hawaiian habit older than Captain Cook's arrival.
Sources: en.wikipedia.org ↗ · blog.bishopmuseum.org ↗ · honolulumagazine.com ↗