This would be Major General Joseph "fighting Joe" Hooker. He succeeded Burnside as the new commander of the Army of the Potomac. Hooker would not be the last general that Lincoln appointed to this post.
general Hooker
There were many generals of the Union to whom it was given a nickname. Hereunder some examples: Grant was nick named "Unconditional Surrender" Hooker was nicknamed "Fighting Joe" Rosencrans was nicknamed "Old Rose"
Major General Joseph Hooker
Joseph Hooker of the Union - commanding the Army of the Potomac.
Fighting Joe Hooker was a Union General.
Major General Joe "Fighting Joe" Hooker was the commander of the Federal Army of the Potomac at Chancellorsville.
"Fighting Joe" (New respondent) No, that was Joe Hooker. It was Burnside's whiskers that got the nickname - Sideburns
Fighting Joe.
Major General Joseph Hooker did not have a middle name but was given the nickname "Fighting Joe" by accident in newspaper "when the hyphen was omitted", newspaper readers loved the nickname and it stuck. Mostly because of his known fighting ability for the Union. At first Hooker himself did not like that nickname, yet through time he liked it more. * In response to the question... "might have been confused with General Joseph (Eggleston) Johnson, whom was harshly branded the nickname "Retreating Joe" because he lacked aggressiveness during the Civil War loosing more casualties than he took "to which could've prolonged the Confederacy's existence', opposite position of the above Joseph."
Joseph Hooker
Joseph(fighting Joe)
Joseph Hooker. It came from a document where his name was preceded by the word 'fighting', and there was a line-break which made it look like as though he was being dubbed 'Fighting Joe', and the name stuck. Curiously, he did not appreciate his new nickname. 'Fighting' was not regarded as a good attribute for a General. The rank-and-file would often be jailed for fighting. It suggested a rowdy individual.