Seven Deities of Good Fortune
Ebisu (left) holding a fishing stick
Ebisu is also one of the Seven Deities of Good Fortune (Shchifukujin in Japanese), widely worshiped from the 15th to 16 century (late Muromachi Era).
Still popular was the custom in the Edo period of placing a picture of the seven gods, aboard treasure ship (like the picture atop), under one's pillow on the night of 1 January to guarantee that first dream of the year would be a lucky one.
Currently people continue to observe the custom including the visit to the shrine to which each god is offered for worship on the new-year days.
The six gods, except the only female god named "Benten", are male and have a strong tendency as being disabled. The people in the Edo period have already pointed out that they apparently have some disability such as a mental deficiency; Ebisu being deaf.
It implies that a person with foreign or unusual appearance because of the disability was believed to be powerful over the ordinary people at that time.
By the way, "Yebisu", a branded Japanese beer, is named after Ebisu.