- Weapons
- Spears and shields are ancient or medieval; pikes and early guns 1500–1700; neat ranks of muskets 1700–1850; machine guns and barbed wire from 1914.
- Uniforms
- Bright coats and tall hats mean the age of muskets. Khaki and field grey arrive around 1900–1915; camouflage patterns are mostly after 1940.
- Fortifications
- Tall thin stone walls are medieval. Low angled star forts answer cannon from the 1500s. Concrete bunkers belong to the 20th century.
- Machines
- Horses and wooden ships before 1850; ironclads and railways after; tanks from 1916, aircraft overhead from the First World War onward.