Arthur and Guinevere

"Just... Live for me, Arthur, that's all I ask right now."

- Gwen to Arthur Arthur and Guinevere were friends and love interests. They cared very little for one another at the start of the series, as Gwen believed Arthur to be an immature bully and Arthur barely seemed to be aware that Gwen existed. As time went on, however, they grew to be friends and eventually fell in love. Though their courtship was complicated by their differing social classes (and later by interference from Morgana), they were ultimately married in the final episode of series 4.

First Impressions
Arthur and Guinevere interacted very little at the start of the series, partly because of their differing social statuses and partly because they had no interest in doing so. Gwen in particular cared little for Arthur at this point. She thought of him as little more than an arrogant bully, and though she seemed somewhat supportive of his crush on Morgana (at one point telling Merlin that she hoped Morgana would be Queen someday) she couldn't imagine anyone actually wanting to marry the prince (The Dragon's Call).

Arthur, for his part, appeared to think of Gwen as little more than Morgana's maid and treated her as he would any other average citizen. When her father mysteriously recovered from a plague that no one else had survived, Arthur thought nothing of searching her house and, after discovering a magic poultice beneath her father's pillow, did not hesitate to arrest her.

That said, Arthur had no wish to see her executed for a crime that she did not commit, and spoke up for her when Uther accused her of causing the plague. He pointed out that using magic to save her dying father was an act very different from starting a plague and said that he didn't believe that there was evil in her heart. He later accompanied Merlin and Morgana to the underground reservoir to kill the Afanc that was contaminating the water supply, which proved that Gwen was not responsible for the plague (The Mark of Nimueh).

Sometime later, both Gwen and Arthur helped Gaius to care for Merlin after he drank poisoned wine seemingly meant for Arthur. When Gaius discovered that he needed a Mortaeus Flower to create an antidote, Arthur journeyed to the Forests of Balor in search of one. He did so against his father's orders, however, and was arrested and taken to the dungeons immediately upon his return.

When Gwen learned what had happened, she helped Arthur smuggle the flower to Gaius by posing as a servant sent to bring him food. Conscious of the guards outside his cell, Arthur hid the flower on his plate and then pretended to be disgusted with the food she'd brought, ordering her to take it away. Comprehending his plan almost immediately, Gwen hurried from the dungeons with the flower in hand and delivered it to Gaius in the nick of time (The Poisoned Chalice).

Friendship
In season 1 Guinevere was shown to think Arthur was rude arrogant and conceited but later in the season explained she also thought he was a strong save the world kind of man and since has been shown to have a crush on Arthur but as a servant is not allowed to say or do anything about it. Guinevere always showed kindness to Arthur and soon enough Arthur fell in love with Guinevere as well.

In season season 2 episode 10 "Sweet Dreams" Uther is discussing a peace treaty with another king whos daughter "Lady Vivian" Is his pride and joy and if any man touched her it would ruin the peace treaty. A third party king who would be poor if the war ended asked his servant to enchant Lady Vivian and Arthur to fall in love.



When they do Arthur says to Merlin to send flowers to his love not specifying Lady Vivian Merlin places flowers and a note which says "All the barriers that keep us apart cant beat the power of true love - Arthur" Gwen is overjoyed and tells Merlin she is having the best day and that sometimes when you think everything is lost so mething happens to give you hope. Gwen leaves a note in Arthurs room unsigned that tells him he can have a second c hance and to meet her in her room. However she leaves it unsigned and Arthur  goes to lady Vivians room leaving Gwen waiting there until her candle goes out and Gwen is in despair. However Merlin tells her the only way to break the enchantment is to give him a kiss from his true love gwen kisses him and Arthur is returned to normal and saves Camelot from War. Proving Arthur is Guineveres true love and Guinevere is Arthurs. In season 2 episode 13 Arthur saves Gwen’s life

In season 3 episode 3 Gwen farts in front of Arthur

In season 3 episode 5 Gwen cries in Arthur’s arms

In season 3 episode 10 "The Queen of Hearts" Morgana has a dream of Guinevere being crowned Queen of Camelot and in pain and jealousy decides to reveal their relationship to the King. She encourages Arthur and Gwen to spend time together. While Guinevere and Arthur are together, she encourages Uther to go for a horse ride and they "coincidentally" come across the two in the woods.

Later in the palace Uther laughs, and saying he too in his past understood the incitement of serving girls, but explained they may never see each other again. When Arthur continues to demand he is in love with Gwen, Morgana hides a magical pouch full of herbs under Arthur's pillow framing her of enchanting him. She is put to death and the two share one last desperate and beautiful kiss as she is taken away.

Before, however, she could be killed, with the help of Merlin Gwen escaped.

Later in the season...

In season 4 episode 9 "Lancelot du Lac" Arthur had asked Guinevere to marry him when Morgana found out she would do anything to keep a serving girl from her throne. Morgana uses necromancy to bring Lancelot back. then using magic brought back Gwen's feelings for him. Gwen and Lancelot are caught by Arthur who is furious and almost kills Lancelot but Gwen stops him, Gwen is thrown in jail. Crying, she throws off the enchanted bracelet from Morgana which caused her unnatural attraction to Lancelot. Afterwards to save Gwen from being put to death like his advisers suggest Arthur tells Gwen to leave camelot and never return. She asked where she would go but Arthur told her he didn't know. Arthur was so blinded by jealousy rage and heartbreak he sent her away. There was nothing else he could do. This was the lowest point for Gwen and Arthurs relationship.

Season 4 Episode 13 "The Sword in the Stone Part 2" Gwen and Arthur at long last marry. After seeing Tristan's lover die in his arms he realizes he cannot lose Gwen again. Arthur comes to Gwen as she is cleaning a room and asks her to marry him, as he never stopped loving her. She responds, "yes" with "all her heart".