My research leads me to believe this to be one of the variants of the British Pattern 1855 Land Transport Corps, Private's Hanger, but admittedly could have been made for one of the many European countries using similar patterns at the time. Some of these are known to have doubled-edged short blades, but this variant has a single-edged mid-length blade.
This example was manufactured pre-1884, and bears the manufacturer's mark "Knight's Head" of Kirschbaum, Solingen, Germany, circa 1855-1883 (Kirschbaum merged with Weyersberg in 1883 and thereafter used a different logo, the Kirschbaum "Knight's Head" and the Weyersberg "King's Head") side-by-side.
Based loosely on the "French M1831 Foot Artillery" and the "US Model 1832 Foot Artillery Sword" Foot Artillery Swords (which in turn was based on the Roman gladius).

Overall length is ~28-1/4";

Hilt is ~5-3/4" in length, one-piece, and is cast entirely of brass; crossguard is ~4" in width and ends in concentric circle finials, 5 complete circles, including the outer edge circle. Grip has 26 raised ribs (as does the French 1831). Pommel ends in a knob with peened blade-tang.

Straight, single-edged (stopped at ricasso), un-fullered blade is ~22-3/8" in length, ~1-3/8" wide at ricasso, reducing in size and ending in a double-edged tip (~5" false-edge); ~5/8" ricasso.
Ricasso is marked on the obverse (right side) with the manufacturer's logo "Knight's Head" (Kirschbaum); and - on the reverse (left side) - with the inspector's mark: a "crown" over inspector's unique number "16" (this is not the manufacture or inspection date as is commonly assumed in error) and the British marks - facing "broad arrows" -> <- which are believed to mean "for commercial sale" or "export". Could these have been produced for sale to the U.S. and C.S. during the American Civil War?