Katsushika Ōi Makes the Night Visible

During the late Edo period, the artist Katsushika Oi pursued painting both alongside her father, the renowned ukiyo-e master Katsushika Hokusai, and under her own professional identity. Born around 1800 to Hokusai and his second wife Kotome, Oi, also known as Ei, initially trained in her father's workshop as an apprentice. She subsequently broadened her artistic study under the painter and printmaker Tsutsumi Torin III, absorbing techniques that would later distinguish her surviving independent output.

While studying under Torin, Oi met fellow apprentice Minamizawa Tomei, whom she married in 1824. The marriage collapsed after only three years, dissolving in divorce. Accounts circulating in later periods attributed the separation to Oi's open ridicule of Tomei's artistic abilities, though such anecdotes reflect popular reputation rather than administrative record. Oi returned to her father’s residence and did not marry again.