In this episode of The Debrief we speak to resident history expert Stuart Dowell, who explains how a gold and diamond necklace which the French leader gave his Polish mistress failed to sell at auction.

The original receipt that came with the necklace shows that it was purchased in Breslau, now Wrocław, on 4 May 1810, just six days before Walewska gave birth to their lovechild.

Read the full story here.