A year after the failure of _The Pioneer_, Lowell published a second volume of poems. In this collection occur the poems _The Legend of Brittany_; _Prometheus_, a poem founded on the old Greek myth of Prometheus, who incurs the wrath of Jupiter by giving fire to mankind; _The Heritage_, a stirring ballad, and _The Shepherd of King Admetus_, embodying the myth of the coming of Apollo to King Admetus and his gift of poesy to the world. The volume heralded the fame that Lowell was afterward to attain as a poet.
In 1846 the Mexican war was the great political question of the day, and the country was divided in opinion as to whether the Government had undertaken the war in a spirit of justice, or merely for the sake of acquiring new territory. The South mainly favored the war, while a portion of the North opposed it on the principle that the new territory would favor the extension of slavery. There was much talk of glory, and the heroes of the day were the generals and soldiers who were winning laurels on the Mexican battle-fields.
Lowell considered the war dishonorable and opposed to the principles of liberty, and he took a firm stand against it. He did this, not, as may be said, in his own way, for the way was new to him, but in a manner that turned the vaunted heroism of the day into ridicule, and appealed to the public conscience by its patriotism and honesty. Keeping his own personality in the background, Lowell sent his wits roving into the world of memory and brought from it a hero who was destined to rival in fame the leader of the Mexican campaigns. This hero possessed the old courage, fire, and enthusiasm which had braved the British in Revolutionary days. His patriotism was a pure flame, his wisdom that of the builders who had founded a commonwealth of civil rights in the midst of the primeval forest; his common-sense would have made him a king in Yankeedom, and his humor was as grim as that of the old Puritans, who believed in fighting the devil with his own weapons. He came on the scene dressed in homespun, and spoke the homely dialect of New England, that singular speech so unlike any other and which seems to have had grafted upon the original English all the eccentricities which made the Puritans a peculiar people.