The rageful behemoths are one of the most iconic and fun classes in Dungeons & Dragons. They're notorious for being the strongest class at low levels, and they can be beautiful tanks and damage dealers. With that said, every good character needs a fun backstory to back them up, regardless of how many pages you wish to write. Thus, we're here to ensure no creativity blocks will stop you from having fun.
Let us talk about concepts that you can use to kickstart your backstory. You can even mix them if you believe your character fits in more than one and create your ultimate warrior.
10 Clan Warrior
Here is a common but also efficient concept. A fighter from a clan is a perfect fit for a Barbarian, and there are many ways you can go about it. It can be a small clan you're trying to help or a big clan that doesn't need you there. You can be one of their best warriors or one of their worst, leaving to save them or to find a better place for you.
You can also use this idea to start a revenge story, where someone destroyed your clan, and now you seek the one behind it. Aesthetically, you can base them on Norsemen, Tribal warriors, and so on.
9 Gladiator
Someone who is a fighter for entertainment value is another great fit for a Barbarian. It's an easy way to justify your combat prowess, and, depending on what you're going for, you can also make a tragic story of someone who's been forced to fight to entertain others.
You can even use this as an excuse to roleplay weird fighting styles, as you're not just a warrior but one that fights in extravagant ways. It's also a fun fit for a Grappler build so that you can justify unarmed combat in your backstory, in case you don't wish to rely on items as much.
8 Zealot
If the world you're playing in has any evil Deities - and it probably does - then an angry berserker can be an excellent fit for a follower. You could work as a zealot for a God of war or similar concepts, so you have an 'honorable' reason for your killing.
You can either be a solo follower, working like an Avatar of the God you follow or be part of some cult that worships them, giving yourself a power base and NPCs to help you on your quest.
7 Survivor
You were someone with a happy life - a commoner, merchant, perhaps even a noble. However, you were faced with the destruction of everything you knew, and everyone you loved died. You wish for vengeance, but that's not your immediate concern. You are young and weak; your only problem is what you'll eat right now.
A character who had to endure most of their life in solitude, building up their rage as they desire comeuppance to those who have wronged them. It's a good fit with most other entries here, too.
6 Raised In Nature
In case you want to do something similar to the previous entry but without all the tragedy and drama. Your character's blunt ways can be nothing more than how they've learned to be, raised by animals or - if you don't want to be that absurd - sentient creatures that live in a forest.
You get to be one of them, justifying more uncommon species such as a Minotaur, or you were found as a baby. Either way, it opens up some fun roleplaying opportunities, with your character not understanding how they're supposed to behave in cities.
5 War Veteran
Soldiers are good concepts for most characters; there's even a soldier background to give you skills and whatnot. Barbarians are a fantastic fit for soldiers, but you can take it one step further by making your character someone who's already gone to war and now needs to live with the heavy memories.
They can be traumatized by such an event, and your Rage can be your body reliving the horrible moments you had to endure in the war.
4 Rebel
A warrior who wishes to free their people and being oppressed by an evil King, Emperor, or whatever you came up with turned them into a rageful fighter. It's also an easy concept to mix with others here.
The only thing to watch out for is that this concept heavily affects world-building. To kill an evil Emperor, there needs to be an evil Empire somewhere. If that fits the world the DM created, or they're on board with adding a place like this, then go for it.
3 A Monster Within
Now, what if we give your Rage a more complex meaning? Instead of losing their cool in combat, you could be someone who has some entity trapped inside you, one who takes over in life-or-death situations, making you more resistant and powerful in the process.
That also gives you a roleplay challenge of being two characters in one, each with their unique personality traits and behaviors. Alternatively, you can make your character have actual anger issues, and their character arc is about controlling that for good.
2 Cursed
Another concept to fit your Rage into your narrative is to make it a curse. It's similar to anger issues, but it's not from trauma this time. Instead, someone made you incapable of controlling yourself when angry, and your job is to get rid of this curse.
Roleplaying can be complicated in this area because this gives you an opening to attack allies and be all like, 'This is what my character would do.' Still, if you talk to everybody beforehand and they're on board, it can be a fun experience.
1 Swap Your Rage For Something Else
Why do you have to be a rageful combatant? Why not swap Rage for something else? Not the class feature, but its concept and how it works for your character. As long as the change is aesthetic, your DM will probably not care.
For example, you could have a Focus mode, where you concentrate on the fight to use everything you've got, allowing you to create a whole backstory around being a calm warrior while still playing as a Barbarian. Or maybe your Rage is an actual transformation, with animal-like features or a magical aura around you. It's okay if not all class features fit the idea perfectly as long as the character is interesting enough.