A rebel soldier is someone who serves in a military function, usually in an unauthorized, or perhaps even illegal operative form. Since most rebellions work in opposition to an established governing body, their existence is generally not recognized in a legal forum, though their actions are acknowledged, and often admonished by these same governing entities.
Examples of rebel soldiers may be found in movies such as the Star Wars film series. The Alliance to Restore the Republic, also referred to as the Rebel Alliance, fought against the tyranny of the First Galactic Empire. The Rebel Alliance eventually evolved into the New Republic, but splintered off again decades later as an armed Resistance to the First Order. Rebel Alliance soldiers can be seen as background characters at the Rebel base on Yavin IV in Star Wars Episode IV: A New Hope, though most of these were seen as X-wing fighter pilots. Infantry troops served during the ground assault at the Battle of Hoth in Star Wars Episode V: The Empire Strikes Back. These soldiers were seen outfitted in special insulated attire suitable for combat in the planet's frozen environs. Other infantry soldiers, many of whom were perhaps the same Rebels who served during the Battle of Hoth, were part of a ground assault force deployed to the forest moon of Endor a few years later to shut down a shield generator bunker so the Rebel fleet could mass an attack on the Empire's newest space weapon, the Death Star II.