US Grant served in the Mexican War. His position was in the Quartermaster Corps. As an aside, Grant wrote later that he was against that war and saw it as a "land grab" by the US.
General-in-Chief of the Union armies
Ulysses S Grant.
US Grant was made Lieutenant General in early 1864. He relocated to Washington DC and had the role of general in chief. Grant made his battle headquarters in northern Virginia and as the Spring of 1864 approached, Grant made plans to oversee Union military operations against Southern General Robert E. Lee. In Virginia Grant was in charge of all Union armies and especially gave orders to the generals like Sheridan who commanded the Army of the Potomac. Grant either informed his Virginia generals to either attack or retreat and in his role he was the defacto leader of the Army of the Potomac and the several other Union armies.
He surrendered to Grant commander of the Union army to end the civil war.
General John A. Rawlings had become a member of US Grant's staff in the Western Theater. He was a close friend and advisor to Grant and helped him with Grant's frequent bouts with alcoholism. Rawlings reports that US Grant fell into a depression over the many disappointments in the Overland campaign and returned to drinking in July of 1864.
He was a general.
Many US Civil War historians believe that General US Grant clearly influenced the outcome of the war, however, that his role did not determine the end result of the war. Until the nearly the very end of the war, Confederate armies were still able to take the field against the Union armies. Southern defeats prior to Grant being named as general in chief, actually influenced the way in which Grant began to conduct the war. This in no way reduces Grants standing as a successful general, it simply clarifies his role and its influence.
he served in the union as a general
When President Lincoln appointed General US grant to the position of general in chief, it created two new elements in the Union' high command. Grant became the chief of staff to President Lincoln and the former general in chief, Henry W. Halleck became Grant's chief of staff. Halleck was well adapted to this role and operated the army's headquarters efficiently and effectively.
Union General William Patterson is most famous in his role in the US Civil War Battle of the First Bull Run. He had, however, served in earlier US wars. He was involved in the War of 1812, and also served in the Mexican War.
general for the north
He was a great general for the North and latter became president.