At the age of 12, his father sent him to work in a bookshop and lending library, a popular institution in Japanese cities, where reading books made from woodcut blocks was a popular entertainment of the middle and upper classes. At 14, he worked as an apprentice to a woodcarver, until the age of 18, when he entered the studio of Katsukawa Shunshō. Shunshō was an artist of ukiyo-e, a style of woodblock prints and paintings that Hokusai would master, and head of the so-called Katsukawa school. Ukiyo-e, as practised by artists like Shunshō, focused on images of the courtesans ("bijin-ga") and kabuki actors ("yakusha-e") who were popular in Japan's cities at the time.