Eddard Stark, popularly called 'Ned' by his family and close friends, is the head of House Stark, the Lord of Winterfell and the Warden of the North at the start of A Song of Ice and Fire. Eddard is a POV character in A Game of Thrones.
Eddard became Lord at the deaths of his father Lord Rickard Stark and his older sibling Brandon Stark. They were executed by Mad King Aerys, for demanding justice in the kidnapping of Lyanna Stark by Crown Prince Rhaegar. Eddard had been fostered at the Eyrie by Jon Arryn along with Robert Baratheon. Robert's Rebellion began when Jon Arryn was told to seize his two wards for the King's justice, instead called up his bannermen.
King Robert Baratheon rides to Winterfell at the death of his previous Hand, Jon Arryn , to ask him to take up the position. It is an honour Ned does not want, but is obliged to accept. He also takes the position so he might investigate Jon Arryn's death when it is said he has been murdered. This leads him to eventually find all of Roberts base-born children, and also discover that Joffrey is not the true son of Robert, but rather born of incest. When he learns this he warns Cersei to flee with her children before he tells the king. Eddard knows that Robert's rage will be so great that he will order all of them killed. However, Cersei has arranged for Lancel who is Robert's squire to give the king, who is hunting, wine that has been made several times stronger. Robert is killed in a hunting accident and Joffrey is made king.
Eddard had been named regent by a dying Robert, but Cersei rips up the proclaimation. Ned tries to deny Joffrey the throne, as he knows that Stannis is the true heir. Eddard had trusted Master of Coin, Lord Petyr "Littlefinger" Baelish to secure the support of the City Watch, known as the gold cloaks. But Eddard is betrayed by Littlefinger who has decided to support Joffrey. Lord Eddard is taken prisoner and all of his men and household personel are murdered. Eddard is thrown into the 3rd level of Maegor the Cruel's dungeon. He had written a letter to Stannis telling him that he was the heir to the throne. This letter never reaches Stannis as it is seized by Cersei and used as evidence of treason against Eddard.
Sansa pleads for her father's life. She blames his actions on the medication that he was on for his injured leg. Joffrey promises to give him mercy if he will confess to his crimes and proclaim Joffrey as the rightful king. Eddard confesses, because he fears that Sansa will be harmed if he does not. The trial is held publically at the Sept of Baelor. Eddard is to confess and be granted mercy to take the black. It has been arranged by Queen Cersei , Grand Maester Pycelle, Varys, the High Septon, and even Yoren the Night Watch recruiter who is waiting in the crowd.
Despite all this, Eddard is beheaded by King Joffrey I at the end of A Game of Thrones despite having been promised he could go to the Wall for the remainder of his life by Joffrey at the behest of his fiancee Sansa. Eddard is executed by Ser Ilyn Payne using Ice the ancestoral great sword of House Stark. Joffrey later tells Sansa that this was mercy, as he gave Lord Eddard a quick death. His head, along with those of his household who were murdered by the Lannister's orders, were put on pikes on the walls of the Red Keep .
As a gesture of goodwill, Tyrion Lannister sends Lord Eddard's bones back to Riverrun, to his wife Catelyn with a Lannister escort. The escort conceals men there to help Jaime Lannister escape.