Throughout all this period of turmoil, the United States recognized no authority in Mexico but that of the Juarez government. In April, 1864, the French minister at Washington complained that serious complications with France were likely to arise out of grants of land made by "ex-President Juarez" in Sonora to emigrants from California. The French government regarded these grants as illegal and proposed to send forces there to prevent the parties from taking "illicit possession."

In May, 1864, the French government sought explanations in regard to a club formed in New Orleans, called the "D. M. D.," Defenders of the Monroe Doctrine. Mr. Seward replied that the object of the club, so far as the government had been able to ascertain, was to bring moral influences to bear upon the government of the United States in favor of a maintenance of the Monroe Doctrine, but not to act in violation of the law, or of the well-understood governmental policy of neutrality in the war which existed between France and Mexico. Members of the association did, however, actually start on an expedition to Brownsville, but the steamer was taken possession of by United States officials. During the year 1864 constant complaint was made by the French government of shipments of arms to the Juarez government from California and from various points along the Rio Grande, particularly Brownsville, in violation of American neutrality.

Shortly after the surrender of General Lee, several Confederate officers of high position and influence went to Mexico and identified themselves with the government of Maximilian. Dr. Wm. M. Gwin, a former United States Senator from California, organized a plan for colonizing the states of northern Mexico with ex-Confederates. This scheme was the subject of several representations to the French government on the part of Mr. Seward. He reminded them that the sympathies of the American people were already considerably excited in favor of the republic of Mexico; that they were disposed to regard with impatience the continued intervention of France in that country; and that any favor shown to the proceedings of Dr. Gwin by the titular Emperor of Mexico or by the imperial government of France would tend greatly to increase the popular impatience. He further requested an assurance that the pretenses of Dr. Gwin and his associates were destitute of any sanction from the Emperor of France.

Among the most prominent Confederates connected with this scheme were Matthew F. Maury, the distinguished geographer and naval officer, who became a naturalized Mexican citizen and was appointed Imperial Commissioner of Immigration and an honorary councillor of state; and General John B. Magruder, who was charged with the supervision of the survey of lands for colonization. It was hoped that the prominence of these men and the high rank they had held under the Confederate government would, in the general uncertainty that prevailed as to the treatment of the South by the victorious Union party, induce many persons to emigrate to Mexico. Maximilian issued a special decree, September 5, 1865, regarding colonization with a view to inducing Southern planters to emigrate to Mexico with their slaves—the latter to be reduced to a state of peonage, regular slavery being prohibited by the laws of the empire. This scheme was altogether impracticable.

In July, 1865, Maximilian finally made an effort to secure recognition of his government by the United States. On the 17th of July, the Marquis de Montholon, the French minister at Washington, called at the department of state and informed Mr. Seward that a special agent had arrived at Washington, bearing a letter signed by Maximilian and addressed to the President of the United States, a copy of which the marquis presented to the secretary of state. On the 18th, Mr. Seward delivered back the copy of the letter to the Marquis de Montholon, and said that, as the United States were on friendly relations with the republican government of Mexico, the President declined to receive the letter or to hold any intercourse with the agent who brought it. The French government expressed to its representative at Washington its annoyance and embarrassment at this step, and said that Maximilian should have taken measures to learn the disposition of the United States before sending the agent.[228]

Mr. Tucker, in his book on the Monroe Doctrine, makes the statement that Mr. Bigelow, who succeeded Mr. Dayton as minister to France, announced to the French government that the United States would recognize the empire of Maximilian upon the immediate withdrawal of the French troops from the territory of Mexico, but that this statement, made upon the envoy's own authority, was disavowed by the President. This is hardly a correct version of the case. It seems that Mr. Bigelow, in the course of a conversation with M. Drouyn de Lhuys, asked him, "in his own name, and without prejudicing the opinion of his government, if he did not think that the recognition of Maximilian by the United States would facilitate and hasten the recall of the French troops."[229]

On the 3rd of October, 1865, Maximilian issued a decree at the city of Mexico, the first article of which declared:

All persons belonging to armed bands or corps, not legally authorized, whether they proclaim or not any political principles, and whatever be the number of those who compose the said bands, their organization, character and denomination shall be tried militarily by the courts-martial; and if found guilty even of the only fact of belonging to the band, they shall be condemned to capital punishment, within the twenty-four hours following the sentence.[230]

The United States, through Mr. Bigelow, protested to France against this decree, as repugnant to the sentiments of modern civilization and the instincts of humanity. M. Drouyn de Lhuys replied with a touch of sarcasm:

Why do you not go to President Juarez? We are not the government of Mexico and you do us too much honor to treat us as such. We had to go to Mexico with an army to secure certain important interests, but we are not responsible for Maximilian or his government. He is accountable to you, as to any other government, if he violated its rights, and you have the same remedies there that we had.[231]