Within a few weeks after the surrender of Lee, every army and fragment of an army opposed to the Union was dissolved. But meantime Lincoln had been assassinated, and the executive administration of the nation had devolved upon Andrew Johnson. This wrought an immense change in the aspect of national affairs. Lincoln was a strong, wise, conservative, magnanimous soul. Johnson was arrogant, vain, narrow, and contentious. Grant soon established his headquarters at the War Department, and devoted himself with characteristic energy to the work of discharging from the military service the great armies of volunteers no longer needed. Their work as soldiers was gloriously complete. Within a few months they were once more simple citizens of the Republic, following the ways of industry and peace. The suddenness of the transformation by which at the outbreak of hostilities hundreds of thousands of citizens left their homes and their occupations of peace to become willing soldiers of the Union and liberty, was paralleled by the alacrity of their return, the moment the danger was passed, to the stations and the manner of life they had abandoned.

General Grant was the central figure in the national rejoicing and pride. The desire to do him honor was universal. But he bore himself through all with dignity and modesty, avoiding as much as he could, without seeming inappreciation and disdain, the lavish popular applause that greeted him on every possible occasion. In July, 1866, Congress created the grade of general, to which he was at once promoted, thus attaining a rank never before granted to a soldier of the United States. His great lieutenant, Sherman, succeeded him in this office, which was then permitted to lapse, though it was revived later as a special honor for General Sheridan. In further token of gratitude, some of the wealthier citizens purchased and presented to Grant a house in Washington. Resolutions of gratitude, honorary degrees, presents of value and significance, came to him in abundance. Through it all, he maintained his reputation as a man of few words, devoid of ostentation, and with no ambition to court public favor by any act of demagoguism.

But a great and bitter trial confronted him. He had never been a politician. Now he was caught in a maelstrom of ungenerous and malignant politics. All his influence and effort had been addressed to promote the calming of the passions of the war, and a reunion in fact as well as in form. The President, professing an intention of carrying out the policy of his predecessor, began a method of reconstructing civil governments in the States that had seceded which produced great dissatisfaction. Upon his own initiative, without authority of Congress, he proceeded to encourage and abet those who were lately in arms against the Union to make new constitutions for their States, and institute civil governments therein, as if they alone were to be considered. The freedmen, who had been of so great service to our armies, whom by every requirement of honor and gratitude we were bound to protect, were left to the hardly restricted guardianship of their former masters, who, having no faith in their manhood or their development, devised for them a condition with few rights or hopes, and little removed from the slavery out of which they had been delivered.

This policy found little favor with those in the North who had borne the heat and burden of the war. In the elections of 1866 the people repudiated President Johnson's policy by emphatic majorities. When the hostile Congress met, the governments Johnson had instituted were declared to be provisional only, and it set about the work of reconstruction in its own way, imbedding the changed conditions, the fruits of the war, in proposed amendments of the Constitution of the United States, which were ultimately ratified by a sufficient number of States to make them part of the organic frame of government of the Republic.

In these days of storm and stress, General Grant took neither side as a partisan. He stuck to his professional work until he was forced to be a participator in a political war, strange to his knowledge and his habits. Congress directed the Southern States to be divided into five military districts, with a military commander of each, and all subordinate to the general of the army, who was charged with keeping the peace, until civil governments in the States should be established by the legislative department of national authority.

Congress, before adjourning in 1866, passed a tenure-of-office act,—overriding in this, as in other legislation, the President's veto. The motive was to prevent the President from using the patronage to strengthen his policy. This act required the President to make report to the Senate of all removals during the recess, with his reasons therefor. All appointments to vacancies so created were to be ad interim appointments. If the Senate disapproved of the removals, the officer suspended at once became again the incumbent. Severe penalties were provided for infraction of the law. During the recess the President removed Stanton, and appointed General Grant to be Secretary of War. Grant did not desire the office, but under advice accepted it, lest a worse thing for the country might happen.

Johnson hoped to win Grant to his side, and in any event to use him in his strife with Congress to defeat the purpose of the law. While the Senate had Stanton's case under consideration in January, 1867, Grant was called into a cabinet meeting and questioned regarding what he would do. He said that he was not familiar with the law, but would examine it and notify the President. The next day he notified him that he would obey the law. Therefore, when the Senate disapproved of the reasons assigned for the removal of Stanton, Grant at once vacated the office, to the intense mortification and anger of the President, who made a public accusation that Grant had promised to stay in office and oppose Stanton's resumption of it.

The charge made a great scandal, but it did not seriously impair Grant's good repute. Johnson was not believed, and the testimony of the members of his cabinet, regarding what happened, was so conflicting that it failed to convince anybody who did not seek to be convinced.

There is reason to believe that Johnson never contemplated retaining Grant in the office, except to use his name and fame to break down the tenure-of-office act. General Grant's plain common sense delivered him from the snare spread for him by wily and desperate politicians. On February 3, he closed an unsatisfactory correspondence with President Johnson, with these severe words: "I can but regard this whole business, from the beginning to the end, as an attempt to involve me in the resistance of law, for which you hesitated to assume the responsibility in orders, and thus to destroy my character before the country. I am, in a measure, confirmed in this conclusion by your recent order, directing me to disobey orders from the Secretary of War, my superior and your subordinate, without having countermanded his authority to issue the orders I am to disobey."

When Johnson was impeached by the House of representatives, General Grant might, if he had chosen to do so, have contributed much to embarrass the President; but he held aloof, discharging his duties as general-in-chief with constant devotion. He was instrumental in instituting many economies and improvements of army management. He greatly advanced the work of reconstruction, and civil governments were firmly established on the congressional plan in a majority of the Southern States before he became the chosen leader of the Republican party.

Grant had not yet distinctly committed himself as between the Democratic and the Republican parties, although from the time of his break with Johnson, he was more drawn to the Republicans. So far as he had any politics he might have been classed as a War Democrat. Had he definitely proclaimed himself a Democrat, no doubt he could have had that party's nomination for the presidency. He was the first citizen of the nation in popularity, of which he had marked tokens, and of which both parties were anxious to avail themselves. It is little wonder that he came to think that the presidency was an honor to which he might fitly aspire, and an office in which he could further serve his country, by promoting good feeling between the sections. In May, 1868, he was placed in nomination, first by a convention of Union soldiers and sailors, and afterwards by the Republican party, in both instances by acclamation. His Democratic opponent was Horatio Seymour, of New York. In the election he had a popular majority of 305,456. He received 214 electoral votes, and Seymour received 80. Three of the Southern States, not being fully restored to the Union, had no voice in the election.