In 1632, Albrecht von Wallenstein ordered an attack on Suhl as part of a campaign against the New United States. Under the command of Octavio Piccolomini, the Suhl attack was intended to be a simple feint, drawing the NUS military's attention, while a corps of Croat cavalry would raid Grantville.
As expected, a small contingent of Americans under the command of Heinrich Schmidt and Tom Simpson made short work of the Swabian raiders. Although Schmidt was convinced the raid came from Swabian folly, Simpson wasn't so convinced.
From the sidelines, spies belonging to Gustavus Adolphus (in his guise of "Captain Gars") informed him of what was happening. This proved Gustavus's suspicion that the Suhl raid was nothing more than a feint.
Suhl had been a center of weapons manufacturing long before the Ring of Fire, and its gunmakers had a long tradition of selling to anyone who was willing and able to pay, regardless of which side they might be on in any current or future conflict. In January of 1633, this ran up against up-timer notions of patriotism and national loyalty in what became known as the "Suhl Incident".