The strongest poison ever known
Came from Caesar’s laurel crown.

Blake’s couplet turns the laurel—an emblem of classical victory and imperial honor—into an image of moral toxicity. By linking “poison” to “Caesar’s laurel crown,” the lines suggest that the intoxicating rewards of conquest and political supremacy corrupt both the ruler and the society that celebrates him. The “strongest poison” is not a literal toxin but the spiritual and ethical damage produced by empire: ambition, tyranny, and the normalization of violence under the guise of glory. In Blake’s broader imaginative world, such symbols often expose how institutions and public pageantry can mask oppression and inner decay.