When and where were some of the earliest known oil paintings made?

The earliest known examples of oil painting date to at least the 7th century CE. These works were discovered in the ancient cave complex of Bamiyan, Afghanistan, where anonymous artists used oil—potentially extracted from walnuts or poppies—to decorate the caves.12

While these findings represent some of the earliest instances of the medium, the history of oil painting in Europe is recorded only as early as the 11th century. By the 15th century, European painters, such as the Flemish artists Jan van Eyck and his brother Hubert, were using oil glazes over tempera underpaintings to achieve greater depth of color and subtle tonal transitions. It is also considered probable that medieval manuscript illuminators utilized oil glazes prior to this period to enhance their work.13