It is Christmas Day and the speaker hears bells ringing in their wild, sweet, and familiar tones; they signify peace and goodwill to men. He muses that the belfries all over the world, day or night, ring out in these hopeful, sublime tones.
Suddenly, though, the sound of cannons in the South thunder loudly and drown out the carols and the message of peace and goodwill. The speaker is reminded of an earthquake shaking the land, bringing sorrow and fear.
He becomes depressed and concludes that hate is stronger than peace. The cannon mocks the sound of the bells.
The bells ring out louder than before, though, and proclaim that God is neither dead nor sleeping, and that Right will triumph over Wrong and bring peace and goodwill once more.
This is a simple but powerful poem. Essentially, it is the poet hearing the bells on Christmas Day and feeling his hope vanish when he then hears the cannons of the South during the Civil War drown out their dulcet tones. Of course, it is unlikely that at the moment of composition the Cambridge poet actually hears the cannons, so what this poem is about is how powerfully the Civil War and the fear it brought on colored everything else, and how it is difficult to have hope that peace will return. The poet vacillates between hope and despair, ending the poem on a powerful and hopeful note.
The poem was written on December 25th, 1863, at a time when the outcome of the war was not yet clear. Furthermore, Longfellow’s son had enlisted without his blessing and was recently injured with the possibility of paralysis, and his wife Fanny had died two years prior due to burns she sustained when her dress caught fire. Longfellow wrote in his journal the Christmas after Fanny’s death “How inexpressibly sad are all holidays” and a year later wrote, “I can make no record of these days. Better leave them wrapped in silence. Perhaps someday God will give me peace” and “’A merry Christmas’ say the children, but that is no more for me.”
The speaker's despair about the war is no doubt colored by Longfellow's personal grief; the imagery he uses and the mood he creates are dark and dismal. In order to represent the South and the concomitant horror of war, he chooses cannons, describing their “black, accursed [mouths]” and their cacophonous, terrible sounds. He equates this to an earthquake which brings about destruction in the land; using the terms “hearth-stones” and “households” here emphasizes how individuals’ intimate lives and relationships are affected (this evokes his own wounded son and how the war came right into his private home).
The imagery of the earthquake rending and disrupting the very earth is in contrast to the way the bells are described: “rolled along,” “unbroken,” “revolved from night to day.” These words suggest harmony, equanimity, and unity. The thunderous tones of the cannon are also in contrast with the “wild and sweet” bells that sing out “a chant sublime”; it is significant that the cannons have no real words or message to offer—just sound and fury—but the bells have an actual message of “peace on earth, good-will to men.”
The decision to end the poem on a hopeful note is telling. The poem is one of resiliency, of faith, of hope even when things look utterly bleak. It was written at a time where such hope and perseverance were extremely necessary given the Union’s troubles. Longfellow exhorts his readers to remember that even though they are in evil, sorrowful times and it seems as if the Nature herself is cracking under the strain, “God is not dead, nor doth he sleep; / The Wrong shall fail, / The Right prevail.” It is likely that he is also speaking to himself on a personal level, reminding himself that he must have hope that someday his grief will abate and he can feel happy once more.