This interesting dirk dates circa second quarter of the 19th century, and into the mid-1800s.
Produced in the so-called "literary dagger" idiom, the grip is in the shape of a Scott in traditional highland dress. The person implied is plausibly Charles Edward Stuart, also known as the Bonnie Prince Charlie, the [unsuccessful] Scottish pretender to the English throne. In the aftermath of the 1746 battle of Culloden, the Scots were generally prohibited from wearing their claymores and dirks, a reprimand that was eased up in the late 18th century by King George III, who, incidentally, employed many Scots in his Army. The image of the Bonnie Prince Charlie was a popular one amongst the Scottish people, and one they couldn't display overtly. As decades went by, and the players moved on to their respective graves, the painful memories of the usurper and his rebellion were beginning to fade, and by the mid-19th century it wouldn't have been unusual to see more open displays of Charlie's likeness.
Daggers of this style are said to have been produced in France, and it is possible that this particular example was made there as well. 17 cm long blade is rhomboid in cross-section and is blued, gilded and etched. A healthy amount of decoration still remains. Amongst the decorations are military and floral motifs, strands of arms, flags, drums, spears, etc. Panel etchings are done in acanthus and olive branches. Scabbard frog is shaped as a crown atop a shield. Another heraldic symbol is a coat of arms, engraved on the front of the scabbard.