The presidency of Ulysses S. Grant was when Ulysses S. Grant was the leader of the United States from 1869 to 1877. He was the 18th president of the United States. During his time leading the United States, President Grant made sure everyone was treated fairly, and he tried to make sure that everyone had an equal chance to get ahead in life. He also worked to make sure the country was safe and secure. President Grant led the Union Army during the Civil War and was a hero who helped to bring the war to an end.