how did dantes receive his title of the count of monte cristo?

During his fourteen years imprisonment in the Château d'If, Dantes befriends the Abbé Faria ("The Mad Priest"), a fellow prisoner trying to tunnel his way to freedom, who claims knowledge of a massive treasure and continually offers to reward the guards well if they release him. Faria gives Dantès an extensive education. He also explains to Dantès how Danglars, Fernand, and Villefort would each have had their own reasons for wanting Dantès in prison, out of circulation. After years of friendship, and knowing himself to be close to death, Faria tells Dantès the location of the treasure, on Monte Cristo. When Faria dies, Dantès uses his corpse to stage an escape to a nearby island, and is rescued by a smuggling ship. After several months of working with the smugglers, he goes to Monte Cristo. Dantès fakes an injury and convinces the smugglers to temporarily leave him on Monte Cristo, then makes his way to the hiding place of the treasure. After recovering the treasure, he returns to Marseilles, where he learns that his father has died in poverty. He buys a yacht, hides the rest of the treasure on board and buys both the island of Monte Cristo and the title of Count from the Tuscan Government.

Returning to Marseille, Dantès plans his revenge but first helps several people who were kind to him before his imprisonment. Traveling as the Abbé Busoni, he meets Caderousse, now living in poverty, whose intervention might have saved Dantès from prison. Dantès learns that his other enemies have all become wealthy since Dantès was betrayed. He gives Caderousse a diamond that can be either a chance to redeem himself, or a trap that will lead to his ruin. Caderousse murders the jeweler to whom he sells the diamond and is sentenced to life in the prison galleys. Dantès, using the disguise of English Lord Wilmore, frees Caderousse and gives him another chance at redemption. Caderousse does not take it, and becomes a career criminal. Learning that his old employer Morrel is on the verge of bankruptcy, Dantès, in the guise of a senior clerk, buys all of Morrel's outstanding debts and gives Morrel an extension of three months to fulfill his obligations. At the end of the three months and with no way to repay his debts, Morrel is about to commit suicide when he learns that all of his debts have been mysteriously paid and that one of his ships has returned with a full cargo, secretly rebuilt and laden by Dantès.