Youngs Antiques has dated this piece to the 17th Century.
The portrait is of exceptional quality and shows Selden in his prime.
Interestingly this painting is identical to an engraving in the national portrait gallery by Robert Hart 1835 and inscribed - Selden - From a picture attributed to sir peter lely in the Bodleian library, Oxford.

The portrait in the Bodleian library is a oval portrait in a rectangular frame, where as this portrait is painted on a rectangular oak board of which is a near match to the measurements of the engraving. This oil on panel measures 10 1/4 x 8 1/2 inches , the engraving measures 10 3/4 x 7 1/4 inches ,the portrait in the Bodleian library measures 20 3/4 x 17 1/4 inches which is considerably larger.

Is it possible that Lely painted another version of this portrait and this is the original that the engraving was copied from?
The painting has some minor marks and losses to the varnish but over all is in fantastic condition for its age. The molded gilt frame is later and has age related losses and some loose moldings in around the picture which I suspect have been added.
Panel size
Height 26 cm
Width 21.6 cm
Frame Size
Height 37 cm
Width 32 cm
Depth 4.5 cm
Youngs Antiques has dated this piece to the 17th Century.
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