The Internet has a lot of different ideas about what this saber is. The blade says, “W.Walscheid Solingen.” I know they were in Prussia and made blades for the Civil War, not sure if Union or Confederate.
JS: Your sword is no doubt Civil War Era and could have been used by either the North or the South. The pattern of sword is US model 1840 enlisted cavalry saber. This pattern was exported by several Solingen makers to American retailers such as Horstmann & Sons in Philadelphia prior to and during the Civil War.
The first American contract 1840 cavalry sabers actually came from Schnitzler & Kirschbaum (S&K), also of Solingen, for trials of the new pattern in 1842. After those initial few hundred imports, Ames Manufacturing Company in Massachusetts made all the swords of this pattern for the U.S. Army. They were the only government contractor until the Civil War when many more swords were needed, and many firms imported German sabers.
The German Solingen swords had the reputation for being the best in the world and were sold worldwide to many countries. Wilhelm Walscheid's name shows up occasionally on cavalry sabers identified to Civil War soldiers, though I know of no one in particular who was selling them.
The configuration of your scabbard with the two carrying rings spaced about a foot apart is typical of how American cavalrymen carried swords; often, Europeans would only use one sword ring, and scabbards would vary in the shape of the drag.
Your sword appears in nice, "as found" condition with good patina in a well-preserved grip. Often, grips on swords are missing the leather-and-wire wrap which is wound over a cord-wrapped wood base. The rust and pitting on the scabbard, especially near the drag, is typical, and this scabbard has protected the blade for over 150 years.
Dealers typically price well preserved, "uncleaned" specimens like this between $400 and $600.