1820

January

 * 29 - King George III of the United Kingdom of Great Britain and Ireland died.

July

 * 3 - Florence Sundvik was born. (DW: The Curse of Fenric)

Unknown dates

 * A Dalek space capsule crashed in the mercury swamps of Vulcan. It would be discovered by humans 200 years later. (DW: The Power of the Daleks)