The first mentions of Danes are from the 6th century in Jordanes' Getica, by Procopius, and by Gregory of Tours. The first mention of Danes within the Danish territory is on the Jelling Rune Stone which states how Harald Bluetooth converted the Danes to Christianity in the 10th century.[22]
Denmark has been continuously inhabited since this period; and,
although much cultural and ethnic influence and immigration from all
over the world has entered Denmark since then, present day Danes tend to
see themselves as ethnic descendants of the early tribal Danes
mentioned in the historic sources. Whether this is true or not, the Danish Royal Family can certainly trace their family line back to Gorm the Old (d. 958 AD) in the Viking Age, and perhaps even before that to some of the preceding semi-mythical rulers.
What costly mistake did the Confederate make before the Battle of Antietam? They divided their army. The Union army also found Lee's battle plan at an abandoned Confederate camp.