The oldest skull of a Barbary lion found in the UK was recovered in the 1930s by workmen digging the moat at the Tower of London. The skull turned out to be the remains of an animal that was kept in the royal menagerie 700 years ago. A second skull was discovered at around the same time.
Scientists at Oxford and the Natural Histotry Museum determined that the second one of these lions lived between 1420 and 1480. The other dating showed that the older remains were of an animal that lived between 1280 and 1385. So these remains are the oldest for a lion found in the UK since the extinction of wild cave lions during the last ice age.
The sultans of Morocco kept their own lions in a lion garden at various palaces in medieval times. There are even stories (and artistic depictions) of prisoners being thrown to the animals.
http://www.nhm.ac.uk/discover/barbary-lion-skull-from-the-tower-of-london.html