Why did Lincoln place grant incommand of all union armies?

Answer 1

President Lincoln had been impressed with General US Grant's overall accomplishments in the Western Theater. Among all available candidates for the position of general in chief to replace General Henry W. Halleck, Lincoln believed Grant would be a success as general in chief.

Answer 2

Because of his high credibility. Grant had captured Vicksburg - an almost impossible task - which liberated the Mississippi, ending the war in the West. Then he saved the Army of the Cumberland from destruction at Chattanooga.

NEW RESPONDENT

At the end of 1863, thanks to the victories of Vicksburg and Chattanooga, Lincoln and the Northern public opinion were thinking that Grant were the right man to be appointed General in Chief. Also Halleck, who, at that time was covering that commission, suggested Grant's nomination.

But before taking such a decision, Lincoln wanted to know:

1 - what were Grant's thoughts about the "grand strategy" to carry on the war and defeat the South and what were the priorities, which would have to be given for succeeding in.

2 - As the presidential election were approaching, Lincoln wanted also to be reassured that Grant was really a soldier and then had a clear insight of the relationship existing between politics and war.

This to avoid of being faced by an intriguing ambitious (like McClellan) that maybe was trying to take advantage of the great prestige of its victories for his personal political purposes, which would have shown that Grant did not understand this relationship and, in the final analysis of being a bad strategist.

Surveys on these points were carried out discreetly by Halleck and personal friends of the President and reassured Lincoln, who decided to appoint Grant to that high office.

Answer 3

Because he had acquired great credibility by liberating the Mississippi, and then rescuing the Army of the Cumberland from starvation.

He was a successful problem-solver.