For someone who knows absolutely nothing, Jon Snow is a pretty big deal. The bastard of Winterfell has had his own storyline distinctly carved out right from season one (and book one, for those who take their fantasy fiction a bit more seriously) of Game of Thrones, the HBO television adaptation of the bestselling George RR Martin novels. Despite being far removed from the murky politics and betrayals that seem to be the only thing uniting the many households in the seven kingdoms, Snow has remained one of the most integral, interesting and complex persons. And we’re talking about a series with more main characters than you can count on your fingertips.

The fifth season ended in June with the death of the Lord Commander of the Night’s Watch, and that pretty much broke the internet. Snow’s shocking murder at the hands of his brothers kept us well-fed with conversations about what was next – conspiracy theories, alternate endings and cries of “Why! George RR Martin, Why!”

Finally, a few months before the new season will be premiered in April 2016, HBO has teased the world with a poster that features Jon Snow.

The HBO poster that has given fans hope.

This suggests to a great degree that the 998th Lord Commander could very well still be alive. But in a show famous for killing off any character to whom you get emotionally attached, why is it so important for Snow, just one of the few remaining Stark kids, to be still alive? Let’s back up a little bit.

Snow is the illegitimate child of the very honourable Eddard Stark of Winterfell. Despite not being a Stark, he has lived a life worthy of a lord. But unloved at home, and ridiculed for being a “Snow” everywhere else, Jon chooses to leave Winterfell for the mighty and ancient fortification called the Wall, taking an oath to never take a wife and to guard the seven kingdoms from all that lies beyond.

However, life doesn’t get any easier for Snow. In a place crowded by those exiled and convicted from all over Westeros, he is “Lord Snow”. He is still an outcast and an outsider, and manages to find a share of enemies this side of the Wall and beyond.

One of the central mysteries in the books and the show is, who is Jon Snow and who was his mother? What is it that everyone keeps telling him he “does not know”? That, along with the fact that Kit Harrington is as much a crowd favourite as Peter Dinklage’s Tyrion Lannister, makes it crucial that Jon Snow returns – be it as a wolf, a stone-hearted zombie or anything else The Red Woman (more on her later) can conjure for him.

Game of Thrones: Jon Snow.

Here is what needs to be known or confirmed about Snow, making it so very important that he returns next April.

Jon Snow is not a Stark. He is not a Snow. He is the one true king.

All these seasons later, it is still very difficult to believe that the very honourable Ned Stark, Head of House Stark, Lord of Winterfell and Warden of the North, could ever be disloyal to his wife Cateyln Tully. She doesn’t see it, which makes her a horrible judge of character actually. Ned came back with a baby boy he claims to have fathered with Wylla, a maid, but that may not be true.

Fans have devoured the HBO series and the books to find clues they believe Martin has left only for them to put together. It may be that Lord Stark was not Jon Snow’s father at all. He could be the son of his sister, Lyanna Stark and Rhaeger Targareyen. One of the first hints that Martin placed somewhere carefully was ensuring that Jon looks like none of the other Stark kids except Arya Stark, who is said to resemble Eddard’s sister Lyanna. So it could be that Jon is not the bastard of Winterfell at all, but the true heir to the Iron Throne, with more claim to it than even Daenerys, as he is the son of Rhaegar Targaryen.

He is Azor Ahai reborn.

The night is dark and full of terrors. And what’s worse is that Jon Snow is dead. Now, more than ever do we realise the value of The Red Woman, a priestess of the Lord of Light, R’hllor, and a “shadowbinder”, a magician with the power to bind shadows to do her will.

Melisandre is vicious. She has been so from the first time we saw her, whether it was when she set men on fire for not supporting Stannis Baratheon as the one true king, or when she gave birth to a man of smoke to kill Renly Baratheon. Stannis and Melisandre topped the list of the worst characters ever to have been written when she talked Stannis into sacrificing his own daughter for his cause.

But there is a reason she is at the Wall. She is clearly not driven by battle strategy like Stannis, but by something a lot more dark and powerful. She is in search for Azor Ahai, “The Prince who was promised”, the one who will triumph as the long and dreadful winter approaches. Jon has done some pretty massive damage to the White Walkers and is committed to fighting this army that is to everyone’s horror, made up of every man they ever kill. The books make a convincing and lyrical case for Snow to be Azor Ahai, and that is where we now are headed. In Melisandre’s own words, “I pray for a glimpse of Azor Ahai, and R’hllor shows me only snow.” That could be literal, or some very obvious word play.

He is a Warg.

In Westeros, families, loyalties and the sigil, or emblem, on banners determine whether you’ll live another day or not. No banner is as symbolic as the Starks which features the mythical grey dire wolf. The Stark sigil is brought to life when Lord Stark finds a dead dire wolf and her six puppies in the wild, one for each Stark kid, mirroring their lives and symbolic of their journeys to come. Jon Snow’s dire wolf, Ghost is an albino with red eyes. He looks different from the pack, but belongs to the same family, much like Snow. Till now, Bran is the only Stark kid to have mastered the ability as a Warg, which means that he can enter the mind of an animal. Jon too has often shown signs of being able to see what Ghost can, adding credibility to the idea that he and Ghost are bound by a magical mystical bond. One of my favourite theories at the end of the fifth season is that Jon wargs into the mind of Ghost and survives – his consciousness lives and returns to his own cured and healed body, with the help of some serious magic that will make absolute sense this far out in the north.

He is the only protector of the Wall.

Despite seeing it with their own eyes, not many this side of the Wall understand the gravity of an ever increasing army of White Walkers. And now that the brothers of the Night’s Watch have killed Jon Snow one stab through the heart at a time, the kingdom is setting itself up for disaster. Other than Samwell Tarly, who is off to the citadel, Maester Aemon, and the now dead Lord Commander Mormont, it seems that only Jon who sees the urgency of getting the wildlings to their own side. While most of the brothers of the Night’s Watch would prefer that the free folk died, Jon chooses to negotiate.

So Snow could be a Targaryen – the blood of the dragon. He could be the Prince who was Promised, he could be one of three dragon riders or he could be Warg. There is clearly a lot that Jon Snow did not know before he died. Luckily for him, these fan theories make quite a compelling case for his return, one way or another. But for now winter is coming, and April is a long way off.