Edward III should be much better known, Rosie tells Matthew Parris. He not only won great battles like Crecy in 1346. He also championed the flourishing of Perpendicular architecture; he understood the "branding" of England, and introduced the flag of St George; and he was ahead of his time in other ways - he was the first king of England to own a mechanical clock and the first to have hot and cold running water in his bathroom!
The expert is the medieval historian, Lord Sumption. He agrees Edward III deserves to be better known, but is less starry-eyed about his achievements. Edward, Lord Sumption says, was an incompetent diplomat, lived too long, and ended his reign a "heroic failure".

Presented by Matthew Parris
Produced by Chris Ledgard