The Japanese never ate salmon sushi until the 1980s when a Norwegian businessman, hired by Norway’s government to offload excess salmon, made a deal with a Japanese company to sell the fish in its grocery stores, leading to its popularity today.
In Japan, it takes up to 20 years of school to become a sushi chef, which is years longer than it takes to become a doctor.
Wasabi was originally eaten with sushi to kill bacteria and parasites in the fish. Now with better sanitary conditions it’s not needed and eaten just out of habit.
Women have historically been barred from cooking sushi due to a superstition that their hands are too warm.