The Fighter

A human in clanging plate armor holds her shield before her as she runs toward the massed goblins. An elf behind her, clad in studded leather armor, peppers the goblins with arrows loosed from his exquisite bow. The half-orc nearby shouts orders, helping the two combatants coordinate their assault to the best advantage.
A dwarf in chain mail interposes his shield between the ogre’s club and his companion, knocking the deadly blow aside. His companion, a half-elf in scale armor, swings two scimitars in a blinding whirl as she circles the ogre, looking for a blind spot in its defenses.
A gladiator fights for sport in an arena, a master with his trident and net, skilled at toppling foes and moving them around for the crowd’s delight—and his own tactical advantage. His opponent’s sword flares with blue light an instant before she sends lightning flashing forth to smite him.
All of these heroes are fighters, perhaps the most diverse class of characters in the worlds of Dungeons & Dragons. Questing knights, conquering overlords, royal champions, elite foot soldiers, hardened mercenaries, and bandit kings—as fighters, they all share an unparalleled mastery with weapons and armor, and a thorough knowledge of the skills of combat. And they are well acquainted with death, both meting it out and staring it defiantly in the face.

In The Nameless Trilogy World

The Fighter is perhaps the most common of the classes seen in The Nameless Trilogy. Everyone from simple prison guards, town watchmen, or soldiers in the military fall under this category. This is anyone willing to pick up a weapon and train in its proficiency in the defense of themselves or others.
If you are thinking of creating a character with this class, consider the following: The setting of the world is a 1920s-esque world. There are flying blimps, basic Model-T style automobiles, trains, alongside old horse-drawn carriages. Gunpowder and explosives are becoming more frequent in the world since the Tenfold War, and armies are no longer dressing up their soldiers in thick sheets of armor as they once did. But there is still a need for traditional fighters. A gun in the hands of a human may be useful at killing other humans, but the world is full of many dangers, large creatures, and especially the prolific orcs. These monsters don't fall as easily to a bullet, which means squads of soldiers still need someone dressed in plate and wielding a sword and shield to defend them from these alien threats.
The fighter is a respected tradition. Why did your character choose to follow this tradition? Do they have background in the military, a mercenary crew, or a squad of monster hunters? Have they ever been employed on a battlefield or sent into the wilderness as part of an orc-culling crew? These questions and more should inspire the creation of your fighter.

Resources:

• Player's Handbook
• Xanathar's Guide to Everything
• Xanathar's Lost Notes to Everything Else
• Sword Coast Adventurer's Guide

Subclasses:

• Champion (PHB)
• Battle Master (PHB)
• Eldritch Knight (PHB)
• Arcane Archer (XGtE)
• Cavalier (XGtE)
• Samurai (XGtE)
• Dragoon (XLNtEE)
• Runeguard (XLNtEE)
• Purple Dragon Knight (SCAG)