There are a few unique examples of privately (rather than state) owned vessels taking part in naval operations during this period. For example:
- During the American Civil War, some private ship owners accepted letters of marque from the Confederacy and sent their vessels on privateering runs. This was most common in the first year of the war, after which the strengthening of the Union blockade made privateering a less practical business.
- During the Bakumatsu era in Japan, feudal domains like Tosa and Satsuma organized naval forces which were under the ownership of their daimyo rather than the Shogun or the Emperor. For example, the Kaientai: Kaientai - Wikipedia