
1) English-language novel 2) Italian unification 3) Scrimmage attire 4) Tor Books book
Found on
https://www.crosswordclues.com/clue/redshirts
[Italy] Redshirts {in it|Camicie rosse} or Red coats {in it|Giubbe Rosse} is the name given to the volunteers who followed Giuseppe Garibaldi in southern Italy during his Mille expedition to southern Italy, but sometimes extended to other campaigns of his. The name derived from the colour of their shirts (complete uniforms were beyond the f...
Found on
http://en.wikipedia.org/wiki/Redshirts_(Italy)

An NPC that has little purpose other than to die. Commonly used in a Sci-Fi RPG setting. Derives from the classic Star Trek television show in which a security detail wearing red uniform shirts accompanied the bridge crew on adventures, almost always to their regret.
Found on
http://rpggeek.com/wiki/page/RPG_Glossary
No exact match found.