The British King George III was Britain's longest reigning king.
In the last two decades of his reign, he started suffering from Porphyria, also known as the ''madness of King George III.''
His disease became so severe that his son, George IV, became Prince Regent. King George III died in 1820.
In this blog, we show you the coins that were minted during his reign. Well-known is the "Cartwheel" two pence, one of the largest coins ever in circulation with a diameter of 41 mm!
Read more about his coinage, just follow the link: