Jumping into the 1620s…
[The English ballad], The Ballad of Chevy Chase, [tells] the story of a large hunting party upon a parcel of hunting land (or chase) in the Cheviot Hills (a range of rolling hills straddling the Anglo-Scottish border between Northumberland and the Scottish Borders), hence the term, Chevy Chase. The hunt is led by Percy, the English Earl of Northumberland. The Scottish Earl Douglas had forbidden this hunt and interpreted it as an invasion of Scotland. In response, he attacked, causing a bloody battle [where] only 110 people survived.
There are two extant ballads […], both of which narrate the same story. As ballads existed within oral tradition[s] before being written down, other versions of this once popular song also may have existed. Moreover, other ballads used its tune without necessarily referring to [this particular ballad].
This ballad was entered in the Stationers’ Register in 1624. The title is alternatively spelled Chevy Chace. The ballad is generally thought to describe the Battle of Otterburn. Some of the verses correspond to that battle but, not all. The Battle of Otterburn took place in 1388. At that [b]attle, Henry Percy (Hotspur) was captured, not killed. He was killed in 1403 in an uprising against Henry IV.
[A]nother possibility [was] border warfare between a Percy and a Douglas in 1435 or 1436. Henry Percy of Northumberland made a raid into Scotland with 4,000 men. He was met by William Douglas, Earl of Angus at Piperden. There were great losses on each side but, the Scots prevailed.
Over time, and the various evolutions of the ballad, events and personages have gotten confused.
Additional Reading & Sources:
The Naming of Chevy Chase (Chevy Chase Historical Society)
Chevy Chase (Contemplations From the Marianas Trench)
Battle of Chevy Chase (Douglas History UK)
The Battle of Chevy Chase (Luminarium: Anthology of English Literature)
Who or What is Chevy Chase? (The Straight Dope)
Battle of Otterburn (Wikipedia)
The Ballad of Chevy Chase (Wikipedia)
The Ballad of Chevy Chase (A Cappella)
The Battle of Otterburn Ballad