Friends and Allies
Like all Jedi, Kanan deeply respected Yoda and was trained by him as a young boy; prior to Kanan becoming Depa Billaba's apprentice.
At some point, back to when he was known as "Caleb Dume", Kanan was assigned to Depa as her apprentice. It can be assumed that the two had a good relationship, though according to Kanan, she was more strict as a teacher than he was. They fought side by side during the Clone Wars. Depa sometimes gently teasing him about his habit of asking many questions.
During the Execution of Order 66, when clones they fight alongside with turned against them, the two fought back in self-defense, but Depa soon realized that they are vastly outnumbered by the Clone Troopers of their unit. She ordered her apprentice to run while she held them off, but was quickly gunned down by Commander Grey and the rest of the men who once served under her command. Her death would leave Kanan scarred with grief and guilt because he escaped and she did not.
Depa's death is one of the main reasons why Kanan was initially distrustful and hostile towards Clone Troopers; like Rex, Gregor and Wolffe, despite the fact that they removed there inhibitor chips before Order 66 initiated, as well as the fact that they were not a part of the Jedi Purge.
Initially, Kanan did not fully understand Depa's belief that the Jedi have to be willing to sacrifice themselves for the sake of others, until he allowed himself to be captured by the Empire on Lothal so the other rebels could escape.
Kanan met Hera at the planet Gorse and its moon Cynda and revealed himself to be a Jedi, instructed her to keep his secret approximately six years prior to the events of Star Wars Rebels. Hera along with Zeb, was initially the only member of the crew of the Ghost who knew Kanan was a Jedi until the events of Spark of Rebellion.
Kanan gets along with Zeb very well but there's still occasional friction that's positive or negative, despite this, they are good friends, Zeb along with Hera, was initially the only member of the crew of the Ghost who knew Kanan was a Jedi until the events of Spark of Rebellion.
Sabine looks up to Kanan due to his leadership skills and abilities, and possibly share a daughter-father bond with him.
It has been shown that Sabine gets annoyed by Kanan, calling him frustrating. But, when Kanan was captured by the Empire, Sabine showed that she was willing to go to the extreme to save him. The one thing they agree on, is helping Ezra through his troubled past.
Shortly after Ezra join's the crew of the Ghost, Kanan becomes his mentor, training him in the ways of the Light side of the Force. Throughout their time together, Kanan comes to see Ezra as a son or little brother-figure, though despite his respect for Ezra, they do not always agree with each other; like when Kanan is initially unwilling to trust Rex, due to the role the Clone Troopers had in wiping out most of the Jedi Order.
Like the other members of the crew of the Ghost, Kanan does not get along with Chopper at all, due to his selfish nature and constant pranks, as well the fact that he has put Ghost crew lives in danger more than once.
Kanan met Ahsoka when she rescued the Ghost crew from the Empire on Mustafar. It is currently unknown if Kanan and Ahsoka knew each other during the Clone Wars. During Vader's raid on the Rebel fleet, Ahsoka asked Kanan too help her find out who was in the TIE Fighter, where Kanan asked how he could help, which Ahsoka responded with "Just remember your training". After Ahsoka found out that Vader's her former mentor, she fainted in Kanan's arms with him deeply concerned for her safety.
In "The Future of the Force", Kanan asked about Ahsoka when she was fighting the Inquisitors, shown that he's worried about her and was the first one to suggest that they couldn't leave her.
Kanan was saddened when Ahsoka sacrificed herself to give him and Ezra more time to escape from Darth Vader.
Kanan was initially distrustful and hostile towards Rex and his fellow clones due to the events of Order 66. When they went undercover as stormtroopers to rescue Ezra, Commander Sato, and his crew, they managed to work together well in a way reminescent of the Clone Troopers and their Jedi Generals during the Clone Wars. After this, Kanan finally put his animosity towards clones behind him when he gave Rex a salute of respect, which the captain gladly returned.
During the Clone Wars, Kanan heard about Cham from Mace Windu, who spoken highly of the Twi'lek. When they first met, Kanan tries to impress Cham and appears to enjoy listening to his stories. However, like the other rebels, Kanan was used and turned on by Cham and his warriors. At the end, they are shown to be on good terms.
Kanan had a Jedi Holocron that contained Obi-Wan's message; regarding the fall of the the Republic and that the surviving Jedi must go into hiding until the time was right for them to come out of exile, it is unknown if the two had met or knew each other. Like many of the surviving Jedi, Kanan believed Obi-Wan was killed in the Jedi Purge (due to the fact that the surviving Jedi were unable to contact each other, as they have gone into hiding). In "Visions and Voices", Ezra Bridger learned via a Nightsister ritual, that the means to defeat the Sith was "Obi-Wan Kenobi". Kanan was surprised to find out that Obi-Wan was still alive and referred to him as "Master Kenobi", implying that Kanan only knew the latter through his reputation.
Kanan and the Grand Inquisitor became enemies from the moment they met. In their first confrontation, the Grand Inquisitor was unimpressed by his skills, but the more they clashed, the more he found Kanan to be a worthy opponent; in their final confrontation, when Kanan found his resolve, both the Grand Inquisitor and the Jedi gave each other a salute of respect. Upon being bested and deprived of his weapon, the Grand Inquisitor was shocked to be defeated though he warned his conqueror of what the Jedi's actions had unleashed before taking his own life.
Despite them being mortal enemies, Kanan was visibly shocked by the Grand Inquisitor's taking of his own life and in fact felt unconscious regret for not having attempted to save him.
During the Clone Wars, Kanan sensed strong emotions of anger, rage and hatred, implying that he has crossed paths with Anakin once or twice. When Kanan was about to fight with Vader, he sensed a cold feeling when Vader arrived or is nearby; he initially assumed it was another Inquisitor, but to his horror, he deduced Vader is not a Inquisitor but a Sith Lord; due to how powerful the latter's connection to the Force is, and was injured in the battle that followed their confrontation. When Ezra wanted to fight him afterwards, Kanan told him Vader was too powerful and that the only reason they were still alive was because he was playing with them.
In "Shroud of Darkness", It is revealed that Kanan greatly respected and admired Anakin, telling Ezra he was the greatest warrior the Jedi had during the Clone Wars.
Kanan did not trust Maul even though Ezra insisted the former Sith Lord was on their side, and only tolerated Maul when Ahsoka (reluctantly) agreed they could use Maul's aid.
But once Maul made his true intentions known, that he intended to take Ezra away from him, he struck Kanan with his lightsaber, blinding him, and would have killed him had Ahsoka not defended him. Kanan remembered his Jedi training, trusted his senses amplified by the Force, and not only bested Maul but thwarted his plans by sending him falling over the edge of the Sith Temple.