This is an unusual example of a banyan or nightgown for a woman. In the 1650s, the introduction of the Japanese kimono to Western society by the Dutch East India Company started a fashion for these simple loose garments. While it was difficult to import traditional kimonos from Japan, English tailors were soon making them up in the most fashionable silks. The woman’s banyan remained an informal garment throughout the 18th century. It would have been worn over stays and petticoats in the privacy of home, either in the morning before dressing formally for the day or in the evening before changing for bed.
This particular example from the period 1750 to 1770 combines the traditional T-shape of a kimono with the conventional European shaping for a woman’s gown at the back and sides.