There is one “class” of people that sets earlier Dungeons & Dragons apart from most other games, old and new. The Hireling.
Most systems, from GURPS and Cyberpunk, the Dark Eye, Midgard, MERS, Shadowrun, FATE, and up to modern DnD 5e, feature many very Tolkienesque Fellowships: A number of player characters of various origin who come together to slay the bad guys and get the loot. They meet NPCs and talk to them, maybe even establish a web of stable contacts, but when they go out to hunt some orc, they go in small units, a fighter, an elf and a dwarf running through the Westfold all alone, and that’s it.
But older DnD was different. It was a bit more expeditionary. A low level fellowship, alone, would have lost more people much sooner, and would never have made it to Rohan, let alone Mount Doom. Earlier, original DnD brings concerns like carrying things, getting enough food, and being enough people to avoid death by 4d4 dogs or 2d6 crocodiles.
Bolstering the ranks
This is where hirelings come in. They are the a bunch of people in a support train, ready to repair armor and provide more torches, or forage for food in the nearby woods while the adventurers go into the old mine to seek out gold & goblins, or to bring 400 kilograms of gold coins back home — for a price.
The legendary cover of the Player Handbook of DnD 1e shows this: While everyone’s eyes are drawn to the two well-known guys climbing the statue to get out the eye, …
… there is a bunch of other people present with them.
There is lightly armored or unarmored personnel carrying boxes, dragging bodies, guarding the door, while Mr. Clean-Sword talks with a wizard and a thief-like looking character reads a map for a man in plate. The four at the foot of the statue are the most adventurer-looking people in the picture. The rest might well be hirelings.
And there is the special hireling, the hireling who levels and develops with the group: the retainer. Or sometimes called a henchman, even though the word henchman has some sinister undertones. Like minion. Or goon.
Normal hirelings are the camp followers who guard the horses, cook the meals, and carry food and treasure between the dungeon and the town. Retainers are the brave fellows who come right down into the dangerous ruins with the adventurers, commonly dubbed “Red Shirts”, but indispensable to boost firepower, and, yes, of course, soak up some hits, so the main characters don’t have to. Their life expectancy varies wildly between groups and play styles. I have recently heard the harrowing tale of a group who has killed a magic user hireling to give the victim’s spell book to the player character magic user, but that is not a role model. A good and competent retainer is much more than a meatshield, more like a confidante and loyal, or hopefully loyal, brother in arms, who will level slower, but will level and grow with the player character, a dependable aid who brings skills that make the party stronger.
Hirelings are in it for the money. Retainers are in it for the player characters. The important stat to get them, keep them, and motivate them, is CHA.
Indeed, in the early days CHA was not so much meant for seducing tavern maids and to power bard spells, it was used to command and inspire followers to come down into the darkness with axe and shield, to go where giant spiders and vicious hobgoblins have their lairs.
Retainers were subject to moral rolls and could potentially run away to leave the player characters stranded, but a leader with good charisma was able to hold them together and inspire them to hold the line.
5e optional retainers
As mentioned, retainers are not really a common sight in 5e. Although, in theory, they would be there: the DMG describes, as a short aside, the specialists that can be hired short- or long-term to do some task that the character can’t or doesn’t want to do. Tasha’s Cauldron even makes them a mini-game by giving them their very own special “Sidekick”-rules.
That, though, is one of two problems for the hireling:
Firstly, most people have enough to do handling their spells and hit points, so learning a special system just to bring along some extra people who are weak (as the power level of 5e characters is much greater than that of Old School characters), that is a tough sell. Hirelings cost time to manage, hog attention that goes away from character play, and don’t pull their weight in a fight.
Secondly, in 5e the focus has shifted away from economy. For an old school character finding gold and dragging it home through the wilderness back home was the main objective of the game. For a new school character, the personal journey is much more important, and XP have many different sources, many groups even reject XP and level their characters once they reach certain milestones in the story. That gives them the option to be generous and even to scoff at lowly moneyz and sink the whole treasure of the Nibelungs deep into the dark waters like a certain someone in a certain medieval thriller. 5e players also seldom count off their torches, as most of them have dark vision on account of being dragonborns or tieflings, and the handful of humans among them soon find some magic item that fixes their bad eyesight. Thus, the traditional job of the torchbearer is simply obsolete.
Old school parties were an enterprise that needs to be financed. New school parties are friends who love adventure. And thus, in the average modern roleplaying game it is just not smart play to have those extra guys around.
The responsibility of the GM
In the end, if someone wants hirelings and retainers in a game, it is the responsibility of the Gamesmaster to create an environment where having some help around is better than being alone.
That means, if a Gamesmaster/Dungeon Master/Conductor/Referee/whatever you want to call the role wants to have the players handle the responsibility to organise a camp and care for their followers, it is important to make hirelings worth the energy to coordinate them and the money they cost.
To be more precise, it demands the enforcement of encumbrance rules, to question the characters’ ability to each carry six weapons, 40 arrows, two large sacks, eight healing potions, and a man-sized chest while holding a torch and a battle axe, or to ask them where exactly they will sleep …. to go deeper into the details of the environment.