Why is Odysseus telling his tale of his recent battle at the beginning of the story?

At the beginning of the story, Odysseus recounts his recent battle to emphasize his heroic status and the challenges he has faced. This narrative sets the stage for his journey home, showcasing both his bravery and cunning. Additionally, it establishes the themes of struggle and perseverance that permeate his tale, allowing the audience to understand the magnitude of his experiences and the hardships he will continue to endure.