Jean-Etienne Liotard's A Dutch Girl at Breakfast has sold for £4.4m ($5.6m).
The painting highlighted Sotheby's old masters evening sale in London on July 6.
Liotard was a renowned genre painter and portraitist who travelled widely in Europe and the near east during the enlightenment era.
The 2nd Earl of Bessborough, a close friend of Liotard's, acquired the painting in 1774. It has remained in his family ever since.
The auction house explains: "This is the only genre scene of an interior painted by Liotard in oils to remain in private hands…
"Liotard's A Dutch girl at breakfast has to this day remained in the possession of Lord Bessborough's descendants, and has never been offered since on the market.
"This extraordinary unbroken provenance stretching back over two hundred and forty years is matched only by its rarity in his œuvre both in terms of its subject and in terms of its medium."
Jan Brueghel the Elder's Still Life of Flowers in a Stoneware Vase achieved £3.8m ($4.9m).
Brueghel's flower paintings are among the most celebrated of the Flemish baroque era. This example is believed to date to around 1607-1608.
While he used studio assistants in much of his other work, he insisted on painting the individual flowers himself. This authenticity makes his still life paintings popular with collectors.
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