Eric Northman is a fictional character in The Southern Vampire Mysteries, written by Charlaine Harris. The character is introduced in the first novel, Dead Until Dark, as vampire living to be about a thousand years and is included in all subsequent novels.

In the early books, little is revealed about Eric's past. In the ninth book, Dead and Gone Eric reveals details about his human life as a Viking. Furthermore, he was deemed a man at the age of twelve. At sixteen he married Aude, his brother's widow, the couple had six children, but only three were living at the time of his turning, two boys and a girl. Aude and their sixth child died of a fever shortly after the birth when Eric was in his early twenties. It is revealed in the television series that the Vampire King of Mississippi murdered his entire family before stealing his father's Viking crown. In the books, he was ambushed one night by a Roman vampire named Appius Livius Ocella and subsequently turned. In the television series, he was made a vampire by Godric. In the television show, it is also shown that Eric was a Viking prince, while in the novels, Eric says that his father was a chief. The name "Eric" or "Erik" comes from Old Norse and means "One ruler" or "eternal ruler". The name "Norseman" was the name given to people who could speak the Old Norse Language, spoken in the Scandinavian countries, namely Sweden, Norway and Denmark. The name "Norseman" means "man from the north", hence Eric's last name being Northman.

In the first novel, Dead Until Dark, Sookie Stackhouse thinks Eric Northman is a "hunk." Sookie describes him as “handsome, in fact, radiant; blond and blue-eyed, tall and broad shouldered. He was wearing boots, jeans, and a vest. Period. Kind of like the guys on the cover of romance books". He's approximately six-foot-four. When Sookie sees him naked for the first time in Dead to the World, she thinks, “if there were an international butt competition, Eric would win, hands down – or cheeks up.” In the TV series 'True Blood' he is tall with long blonde hair. By the end of the first season, and a little bit into the second, Pam (his progeny) cuts his hair shorter than expected because he gets blood in it. Eric is always shown in dark blue jeans with a black singlet and a black leather jacket. When his hair is cut shorter, he parts it and combs it diagonally backwards. His personality in the series is mostly the same, Eric Northman is ruthless and does not care much for human life. His relationship with his progeny, Pam, is where you see his softer side. When he and Pam face difficult challenges and situations, Eric puts her needs above his own. By the middle of season 2 Eric begins to pursue Sookie Stackhouse because of his interest in her abilities, and by the end of season 2 Eric Northman has cunningly tricked her into drinking his blood. Near the beginning of the third season, it is implied that he is beginning to develop feelings for her, even helping her when it is disadvantageous for him to do so.

Eric is portrayed in the books as being somewhat arrogant, but having a true joie de vivre. He is confident almost to a fault, once reprimanding a thug in the third book, Club Dead, for threatening Sookie and referring to her as his "future lover" although no potentially romantic relationship between Eric and Sookie yet existed. He can be manipulative to suit his needs. He is not above using deceit though it seems to be a last resort when it comes to Sookie. However, he is typically upfront regarding any action he takes and if he is manipulative he is very frank and open regarding his wishes. Due to his frank nature, Sookie comments to herself how she can always know where she stands with Eric. Indeed, Sookie frequently remarks how conversations with Eric are seldom single layered and how he never says something without reason. He is not sentimental in the least but shows a great deal of concern over Sookie and her happiness and well-being, perhaps making the relationship between Eric and Sookie all the more impressive. Sookie believes that, although Eric has created a modest, but thriving business empire and carved out a position of authority in the delicate vampire hierarchy, at heart he remains a born-Viking warrior, ready to leap into battle at any instant.

The vampires in Charlaine Harris' world are organized according to a feudal system with each state divided into "Areas", each of which are governed by a sheriff who then owes allegiance to the queen or king of that particular state. Some states, like California, are so large and so heavily populated with humans (and therefore vampires who prey on humans) they are divided into multiple kingdoms. For example, what humans see as California, vampires see as California Sacramento, California San Jose, and California Los Angeles. Louisiana is not such a state and is ruled by one monarch. However, it is possible for a monarch to control multiple states. At one point in the series Louisiana is controlled by the same vampire who also controlled Arkansas. Later in the series a different ruler controls Louisiana, Arkansas, and Nevada.

Eric is the most powerful vampire in Area Five of northern Louisiana: a territory that includes the small town of Bon Temps. Eric serves as Sheriff of area 5, or local boss, of that area and owns a vampire bar in Shreveport called "Fangtasia," that also serves as his headquarters. He runs the bar with the help of his vampire progeny Pam and a few of his underlings, or vampires who owe allegiance to Eric as their sheriff. Eric takes his responsibilities and role within the vampire hierarchy very seriously. In the sixth novel, Definitely Dead, Eric mentions that he has paid a significant fine to the arbitrator for killing a former Fangtasia bartender, Long Shadow. This demonstrates that he did not hide his crime, as killing another vampire is a "serious thing.". Precisely what a Vampire Sheriff does, aside from owe allegiance to their monarch, do their monarch's bidding, and rule their Area, is still somewhat unclear. Sookie makes a conscious effort not to pry too hard into vampire affairs and Eric does nothing to encourage her learning much more than she already knows. Eric surprised Sookie in the tenth book, Dead in the Family, when he explained the vampire hierarchy in more detail, simply so she, as his wife according to vampire law, was better informed for her safety.

The state of Louisiana was in disarray after the results of Hurricane Katrina, and after the Queen of Louisiana, Eric's hierarch, was crippled in an explosion and eventually killed by the vampires of Nevada under Felipe de Castro's order. Eric was spared since he was the most practical of the Sheriffs and had one of the largest money makers, Bill Compton, living in his area and owing fealty to him. As the last surviving sheriff of Louisiana, Eric pledges his allegiance to the new regime in order to protect those under him, a tactical move that highlights his capabilities both as a leader and a political survivor. Had Eric resisted, he and all of the vampires serving under him (possibly with the exception of Bill) would have been killed, including Sookie. After accepting the new King, Felipe de Castro, he is then allowed to maintain control of his area and his followers when the other sheriffs of Louisiana and a number of their minions were all killed. Under the new regime, Eric has spent a significant amount of time acclimating himself to his new overlords. Despite his oath, however, Eric remains ever vigilant for opportunities to either further secure his position or free himself entirely from scrutiny of Felipe's Louisiana representative, Victor.

The author introduces Sookie to Eric in her first novel, Dead Until Dark. Eric then appears in all the subsequent novels and has either saved or attempted to save Sookie's life in every book. From the second book onward, Eric and Sookie share at least one intimate moment together per book. In the second book, there are several intimate moments: when he asks her to suck out a bullet in his chest that he took for her, and when Sookie invites him to an orgy they have to play the part. In the third book, they almost have sex before being interrupted by Bubba and also when he gives her blood after she is staked. In book four, they experience a sexual relationship when he is cursed with amnesia, which he forgets all about promptly after being un-cursed. In book five, they kiss. In the sixth book, during battle, Eric sneaks a kiss on Sookie after saving her. In book seven, Sookie and Eric exchange blood tying them to each other in a blood bond and Eric kisses her. In book eight, they kiss again after Eric smells fairy blood all over Sookie; and in the ninth book, they consummate their relationship after being wed by vampire laws and seem to be moving in the direction of an official relationship.