From Hickok Sports, a history of archery:

The modern sport of target archery originated in England during the 14th century, when the longbow became the English army's most important weapon, first at the Battle of Crecy (1346) and later at Poitiers and Agincourt. From 1330 to 1414, English kings banned all other sports because they diverted time from archery and a royal decree of 1363 required all Englishmen to practice archery on Sundays and holidays.

[...]

Roving, the predecessor of modern field archery, grew out of casual hunting with bow and arrow. Archers are presented with targets of various shapes and sizes, simulating small animals, and they shoot at unknown ranges over rough ground, not a prepared course.

Such "roving" sounds a lot like modern golf. What lead me to read about ancient archery was this little detail: at the end of a "roving" archery match, the archers would shoot an arrow back toward the location at which they began the course. This would be analogous to hitting a golf ball from the 18th hole back to the 1st tee. Depending on the geography of the course, this could be quite a distance, so often the shot was fired up rather high. It wasn't really part of the competition — just a traditional conclusion.

The upshot of this history lesson is that the concluding upwards shot became known as the "upshot," first in archery, and then as a common metaphor, as it is still used today.