What happened on December 12

Battle during the Byzantine–Sasanian War of 602–628

The Battle of Nineveh was the climactic battle of the Byzantine–Sasanian War of 602–628.

14th-century Greek noblewoman

Maria of Enghien, also known as Marie of Enghien or d'Enghien, was the Lady of Argos and Nauplia in Frankish Greece from 1376 or 1377 to 1388. She inherited the estate from her father, Guy of Enghien, when she was a minor. Her paternal uncle, Louis of Enghien, served as her regent.

U.S. state

Pennsylvania, officially the Commonwealth of Pennsylvania, is a state located in the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Maryland to its south, forming the Mason-Dixon Line, West Virginia to its southwest, Ohio to its west, the Canadian province of Ontario to its northwest via Lake Erie, New York to its north, and the Delaware River and New Jersey to its east. Pennsylvania's most populous city is Philadelphia, and the state capital is Harrisburg.

1861–1865 conflict in the United States

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by states that had seceded from the Union to preserve slavery in the United States, which they saw as threatened because of the election of Abraham Lincoln and the growing abolitionist movement in the North. The war ended with Union victory, the dissolution of the Confederacy and the abolition of slavery, freeing four million African Americans.

1866 British mining disaster

The Oaks explosion, which happened at a coal mine in South Yorkshire on 12 December 1866, remains the worst mining disaster in England. A series of explosions caused by firedamp ripped through the underground workings at the Oaks Colliery at Hoyle Mill near Stairfoot in Barnsley killing 361 miners and rescuers. It was the worst mining disaster in the United Kingdom until the 1913 Senghenydd explosion in Wales.