Hadji Murad has two principal reasons for joining the Russians. In the first place, the Avar leader, Imam Shamil, is holding his mother, wives, and children captive. Hadji hopes to set them free with Russian assistance. He is also eager to avenge other members of his family who have already been killed. Shamil, for his part, is hoping that by taking Hadji's family captive, he will be able to goad Hadji into attacking so that Shamil can kill him.
Shamil holds at least nine members of Hadji Murad's family: his mother, Patimat; his two wives; five young children; and his eighteen year-old son, Yusuf. Yusuf is kept separately from the rest, in a pit with criminals awaiting judgment. However, despite this harsh treatment, Yusuf does not bear the same hatred as Hadji towards Shamil, regarding his father's hostility to the Avar leader as obstinate and futile. Tolstoy even says that Yusuf admires Shamil, in defiance of his father. However, when Shamil commands Yusuf to write to his father, telling Hadji to return and making numerous threats against Yusuf and other members of the family, Yusuf defies the Imam and attempts to escape, albeit unsuccessfully.
The real Hadji Murad had other grievances against Shamil, which Tolstoy does not mention in his fictionalized version of their quarrel. The initial rift was a dispute about who would succeed Shamil as leader of the Avars, a position coveted by Hadji Murad, but which Shamil bestowed on his son, Khazi Mohammad, in 1851.