While other officers and crew members contributed to the oppressive atmosphere, Bligh was the figurehead and his tyrannical behavior, including excessive punishments, verbal abuse, and unfair distribution of food, is what ultimately sparked the mutiny.
It's important to note that the book and the historical event are complex. While Bligh's actions were undeniably harsh and contributed to the mutiny, there were also other factors at play, including the challenges of the voyage and the power dynamics on board.