The two Suma-class cruisers were protected cruisers operated by the Imperial Japanese Navy. While more lightly armed and armored than many of its contemporaries, their small size and relatively simple design facilitated their construction and their relatively high speed made them useful for many military operations. Both participated in combat during the Russo-Japanese War and World War I.

The QF 3-pounder Hotchkiss or in French use Canon Hotchkiss à tir rapide de 47 mm were a family of long-lived light 47 mm naval guns introduced in 1886 to defend against new, small and fast vessels such as torpedo boats and later submarines. There were many variants produced, often under license which ranged in length from 32 to 50 calibers but 40 caliber was the most common version. They were widely used by the navies of a number of nations and often used by both sides in a conflict. They were also used ashore as coastal defense guns and later as an anti-aircraft gun, whether on improvised or specialized HA/LA mounts.