1861

Unknown dates

 * The Confederate States of America came into existence with Jefferson Davis as its first and ultimately only President. (TN: Blood and Hope)
 * The American Civil War began between the United States of America and the Confederate States of America. The War Lords kidnapped several soldiers from this conflict for use in their War Games. (DW: The War Games)
 * The Malicious Damage Act, which covered lighthouses, was passed. (DW: Horror of Fang Rock)
 * The Cemar came to Earth to try to discover some minerals. (NSA: The Good, The Bad and The Alien)

Behind the scenes
According to REF: Doctor Who: The Encyclopedia, Prince Albert of Saxe-Coburg and Gotha, husband of Queen Victoria of Britain, died in 1861.