<P> One of Sherman's main concerns in postwar commands was to protect the construction and operation of the railroads from attack by hostile Indians . Sherman's views on Indian matters were often strongly expressed . He regarded the railroads "as the most important element now in progress to facilitate the military interests of our Frontier". Hence, in 1867, he wrote to Grant that "we are not going to let a few thieving, ragged Indians check and stop the progress of (the railroads)." After the 1866 Fetterman Massacre, Sherman wrote Grant that "we must act with vindictive earnestness against the Sioux, even to their extermination, men, women and children ." </P> <P> Despite this language, there was little large - scale military action taken against the Indians during the first three years of Sherman's tenure, as Sherman was willing to let the process of negotiations play out in order to buy time to procure more troops and allow the completion of the Union Pacific and Kansas Pacific Railroads . During his time as departmental commander, Sherman was a member of the Indian Peace Commission . Though the commission was responsible for the negotiation of the Medicine Lodge Treaty and the Sioux Treaty of 1868, Sherman was not particularly privy in either due to being called away to Washington during the negotiations of both . In one such instance, he was called to testify in the impeachment trial of Andrew Johnson . However, Sherman was successful in negotiating other treaties, such as the removal of Navajos from the Bosque Redondo to traditional lands in Western New Mexico . When the Medicine Lodge Treaty was broken in 1868, Sherman authorized his subordinate in Missouri, Philip Sheridan, to conduct the Winter Campaign of 1868--69 (of which the Battle of Washita River was a part), where Sheridan used hard - war tactics similar to those he and Sherman had employed in the Civil War . Sherman was also involved with the trial of Satanta and Big Tree: he ordered that the two chiefs should be tried as common criminals for their role in the Warren Wagon Train Raid, a raid that came dangerously close to killing Sherman himself . </P> <P> On July 25, 1866, Congress created the rank of General of the Army for Grant and then promoted Sherman to lieutenant general . When Grant became president in 1869, Sherman was appointed Commanding General of the United States Army and promoted to General of the Army . After the death of John A. Rawlins, Sherman also served for one month as interim Secretary of War . His tenure as commanding general was marred by political difficulties, many of which stemmed from disagreements with Secretaries of War Rawlins and William W. Belknap, whom Sherman felt had usurped too much of the Commanding General's powers, reducing him to a sinecure office . Sherman also clashed with Eastern humanitarians, who were critical of the Army's killing of Indians and had apparently found an ally in President Grant . To escape these difficulties, from 1874 to 1876, he moved his headquarters to St. Louis, Missouri, returning to Washington only upon the appointment of Alphonso Taft as Secretary of War and the promise of more authority . </P> <P> Much of Sherman's time as Commanding General was devoted to making the Western and Plains states safe for settlement through the continuation of the Indian Wars, which included three significant campaigns: the Modoc War, the Great Sioux War of 1876, and the Nez Perce War . The displacement of Indians was facilitated by the growth of the railroad and the eradication of the buffalo . Sherman believed that the intentional eradication of the buffalo should be encouraged as a means of weakening Indian resistance to assimilation . He voiced this view in remarks to a joint session of the Texas legislature in 1875 . However he never engaged in any program to actually eradicate the buffalo . During this time, Sherman reorganized frontier forts to reflect the shifting frontier . </P>

Which president was the general in charge of the union army during the civil war