Captain Campion was a high ranking Efrafan officer, an expert tracker, and a Wide Patrol leader. Before the death of General Woundwort, Campion loyally served the tyrant, stopping Blackavar's escape attempt. After the tyrant's death, he became the new Efrafan Chief Rabbit. Under him, the warren lost some of its tyrannical attributes and made a close alliance with Watership Down.
Campion is the captain of the Owsla. He is a brave and skillful officer respected by General Woundwort. He is well liked by both Hazel and Bigwig despite being their enemy for a while. Campion takes over the warren of Efrafa after Woundwort's disappearance, and agrees that Efrafa and Watership Down can co-exist in peace. In Tales from Watership Down, the final chapter is devoted to Campion; he introduces the Wide Patrol to Vleflain and Watership Down and becomes a respected and well-liked leader. He eventually dies on patrol after a fight with a pair of cats, but like Woundwort lives on in rabbit legends, as a sort of guardian angel for rabbits on patrol.
In the film adaption, Campion's role drastically decreases, to the point of becoming a background character with only a few lines. However, some of his actions would become very memorable pieces of the plot, such as the moment when he tells Woundwort that Bigiwg wounded Chervil and took a crowd of the mark with him and when he tells the other Efrafans to run for their lives when he spotted Bob the dog coming to Watership Down. His fate is ultimately left open ended at the end of the film.
Captain Campion plays a much bigger role in the Watership Down TV series than he did in his previous appearences. However, his personality isn't the same as it was in previous adaptations.
In the animated series, Campion sees that Woundwort's leadership is destroying Efrafa, but is torn between his feelings for the free ways of Watership Down and his loyalty to his chief rabbit. In the end, Campion turns against Woundwort to save his friend's warren, yet sacrifices himself to save Woundwort from a falling rock. Surviving miraculously but with terrible scars and losing an ear, Campion is touched by the Black Rabbit of Inlé and is tasked with stopping Woundwort. Feeling empty and half-dead, Campion's will to live is returned thanks to the love of Blackberry. He finally settles with her on Watership Down, not only because of his love for her, but because he also had no other place to go after Efrafa was destroyed.
In the TV series, Campion is probably the most conflicted character. On one hand he has a strong sense of loyalty to General Woundwort. On the other he knows that Woundwort is a brutal tyrant. Campion is grateful to Hazel for helping him to recover from a hawk attack and becomes a double agent for Watership Down. However, he is very lonely and although he knows that he is doing the right thing, he still feels guilty for betraying Woundwort who both trusts and respects him. Campion's guilt results in self-loathing, and perhaps even suicidal tendencies as he throws himself under a boulder to protect Woundwort, the very rabbit he is trying to dethrone. Even whilst acting as a spy for the Watership Down rabbits, Campion still maintains an astonishing amount of loyalty to Woundwort and saves him from the shining wire, before being arrested by Vervain immediately afterwards, and very nearly gets himself killed in order to protect him from a falling boulder. Campion's remarkable sense of loyalty is also shown by the fact that, although he hates Vervain for being a coward and a bully, he still prevents General Woundwort from executing him for cowardice by lying to his chief and telling him that he had sent Vervain on ahead. Ironically, Campion is a very good liar despite also being a very loyal and honourable character. Hawkbit states that he is also too crafty to get caught by Woundwort.
Campion is very brave and willing to risk the wrath of Woundwort in order to act as a double agent for the Watership Down rabbits. His courage is also shown by his willingness to sacrifice his life for Woundwort, despite the fact that he has been working for Watership Down. In addition to his immense courage and loyalty, Campion is, with the possible exception of Moss, by far the most compassionate of the Efrafan Owsla and constantly tries to make Efrafa a better place. Essentially Campion is the polar opposite of Vervain, despite being a fellow Efrafan officer.
Campion has a soft spot for Primrose, having often stood up for her in Efrafa. However, if he did have any romantic feelings for her, they are quickly thrown aside when he meets and falls in love with Blackberry and at the end of the series they settle down on Watership Down together. Campion's noble heart even allows him to gain the respect of the Black Rabbit of Inle, who tells him he has an important part to play in the destruction of Woundwort.
- Campion is Blackberry's love interest of the TV series.
- Campion is voiced by Rob Rackstraw in the series.
- Campion is voiced by Nigel Hawthorne in the movie, though he has few lines.
- In the movie, Campion is the only specific Efrafan rabbit to lack unique characteristics: General Woundwort is larger than all Efrafan rabbits and his left eye is blind, Hyzenthlay has a brighter color than many does and other Efrafan rabbits, Blackavar has very dark fur and scars, Vervain is slightly darker and taller than most rabbits, and Chervil is slightly larger than other rabbits (not as large as Woundwort) and has larger blue circles in his eyes, but Campion looks exactly as most rabbits.