During the American Civil War, the Union was a name used to refer to the federal government of the United States, which was supported by the twenty-three states which were not part of the secession attempt by the 11 states that tried to form the Confederacy. Although the Union states included the Western states of California, Oregon, and (after 1864) Nevada, as well as states generally considered to be part of the Midwest, the Union has been also often loosely referred to as "the North".