Tughril Mahmut's Mother: Although only appearing briefly, it's shown that she and Mahmut cherish each other. When she sacrificed herself to save Mahmut's life, Mahmut initially didn't want her to go, but tried to obey her after she promised to come back to him later. Her, and the whole village's demise, later became a crucial factor in fueling Mahmut's desire to become a pasha, so that the tragedy won't repeat itself in the future.
Sehir Khalil: Because Khalil adopted him as a child after the Tughril Massacre, Mahmut and everyone that he's associated with thought of Khalil as Mahmut's own father. He has a warm and loving relationship with the older pasha, and frequently got various advice in regards of being a better decision maker. However, it doesn't mean that Khalil controlled Mahmut's actions, rather he lets Mahmut move in his own pace, only reminds him here and there when he feels that Mahmut's tendency to make rash decisions will do more harm than good. When Khalil passed away, everyone could tell that Mahmut is suitably devastated, although he tried to put on a tough front by not shedding any tears. At the later part of the story, some of Divan's members thought of him as one of Khalil's successors aside from Zeki, even though by that time his ideology is not that similar anymore with his surrogate father's no-war principle.
Sapka Ibrahim: Mahmut first met Ibrahim after a cirit (horse-riding) game when the former got an injury on his knee after falling off from his horse and the latter has to bring him back to the dorms. As Mahmut's best friend from their time in the Military Academy, Ibrahim's well being is very important to Mahmut, so much that he personally helped Ibrahim when the Divan had deemed him as a traitor and decided to take care of Hisar problem with swift judgement. Mahmut really believes in his dedication as a governor that he immediately decided there must be something wrong when Ibrahim decided to declare Hisar as an independent nation for the Araba tribesmen.
Zehir Zaganos: Mahmut's relationship dynamics with Zaganos keeps changing as the story unfolds: at first, he saw Zaganos as a stubborn war-monger pasha that he found aggravating, especially after Zaganos shot down his opinion to pursue a "third way" to solve Minister Franz's case harshly. This opinion still stayed the same when the story enter Ibrahim's arc, when he first begged Zaganos to stop his plan on taking back Hisar, and got angered when Zaganos didn't listen to him. After he got demoted from his pasha title and met Cyrus, Zaganos somehow already become someone that he unconsciously based his actions on, along with Khalil and Suleyman that he already acknowledged as his role models. Along his travels, he slowly realizes that Zaganos is, in spite of his hard liner stance, is actually really competent and thorough when doing his job, that Mahmut often felt that he's nothing compared to the older pasha. Even so, when Zaganos decided to abandon Acayip in the Civil War arc, he still couldn't accept that decision, and decided to use his authority as the mission's executor to deal with the aftermath of the civil war in his own way, without consulting the Divan, and by extension Zaganos, first about his decisions there.
After the civil war between the Four Stratocracies, it could be seen that Mahmut's relationship with Zaganos had softened a bit, no longer based on belligerence, but rather on silent acknowledgement of each other's capabilities. But, in chapter 87 it's revealed that actually, after all of this time Mahmut still can't erase his inferiority complex to Zaganos. He put himself in harm's way to save Zaganos' troops from Sud Army's surprise attack, moving his troops from Chielo to Religion in a meager time span of three days. Then he went further by lunching himself to halt Frentzen's carriage in the middle of Sud Army's tight formation, then dueled with Frentzen when the latter tried to kill Zaganos. He desperately told Zaganos that he "wanted to be (like) Zaganos," because he felt that both him and Khalil are unable to stop the war, and Zaganos is the only one that can stop it. In later chapters as Turkiye's troops began to advance to Murs, Mahmut's faith on Zaganos is being tested multiple times by the latter's various callous strategies such as his disregard for Mahmut's opinions despite of his official position as his second-in-command and his use of cannons when attacking Murs. However, until now Mahmut still decides to go along with Zaganos' strategies, as he still can't figure out the latter's real objective.
Shara: Mahmut met her in the celebration of Sheker Bayram at Altun when he hung up with Ibrahim, who visited Altun on Zaganos' request. They started off nicely, even when Mahmut is clearly a bit uncomfortable because of her kind of over-the-top way of communicating with him. After the party was over and Mahmut went back home, he found Shara sprawled on his bed sleeping, then got promptly shocked and proceeded to wake her up. Turns out, she went to his house to give him his poetry book, which he left unintentionally in the party. When he went to Hisar in order to save Ibrahim, she tagged along with him because Ibrahim is also her friend, and he just let her, albeit a bit grudgingly. She helped him along with the costume for their infiltration into the city, and also assisted him in his quest to free Hisar's citizens held captive by Rod Orm. After his demotion, Mahmut went to Oasis, where he met her and ended up helping the Oasis shurta in solving a case of murder that targeted people connected in the production of a dance performance.
After they parted way at Oasis, they didn't meet again until Mahmut went to the four stratocracies of Turkiye, when he asked for her assistance to spread propaganda to the citizens in preparation for the upcoming insurgence. At that time, he told her to keep spreading the propaganda even if he ended up not making it back alive, in which she replied by asking him not to die in an easy demeanor characteristic of her before they parted way.