This portrait (P534) looks like the work of an Anglo-Netherlandish painter. In 1969, Sir Roy Strong proposed that it might by Steven van der Meulen (d. 1563/4), an Antwerp-trained artist who was working in London by September 1560. Early in 1561, van der Meulen was sent to Stockholm to paint the Swedish king Erik XIV, who was a potential suitor to Elizabeth I. The resultant portrait was presented to the queen in June 1561.
Numerous portraits of Robert Dudley have been attributed to this artist and his workshop, including likenesses at Waddesdon Manor and the Yale Center for British Art. However, his actual output remains unclear. He died in 1563 or early 1564, as his will was proved on 25 January 1564.