Short answers, pulled from the story.
Claudius Gothicus, born Marcus Aurelius Claudius and also known as Claudius II, was Roman emperor from 268 to 270. He is best known for decisively defeating the Goths at the Battle of Naissus, a victory that earned him the surname Gothicus.
Claudius Gothicus ruled from 268 to 270, after being proclaimed emperor by his army following the death of his predecessor, Gallienus.
Claudius Gothicus died after succumbing to a pestilence, possibly the Plague of Cyprian, in August or September of 270. Historians disagree on the exact month, dating his death variously to January, April, August, or September based on conflicting ancient sources.
At the Battle of Naissus, Claudius and his legions routed a huge Gothic army, taking thousands of prisoners and destroying the Gothic cavalry as a fighting force. He fought alongside his cavalry commander, the future emperor Aurelian.
A legend recorded in works such as the Golden Legend of 1260 and the Nuremberg Chronicle of 1493 claims a Roman priest named Valentine was beheaded under "Emperor Claudius" in 270. Since Claudius I did not persecute Christians, tradition assumes the emperor in the legend was Claudius Gothicus, or Claudius II.
The Historia Augusta and other later sources claim Claudius Gothicus was connected to Constantine the Great's family through a niece named Claudia, said to be the mother of Constantius Chlorus. Historians suspect this genealogy was fabricated to link Constantine's family to a well-respected emperor.