The Civil War became imminent as the support of Southern rights and secession sentiment grew. Alabama left the Union on January 11, 1861 when the state’s second constitutional convention passed the ordinance of secession. The Confederate government was organized at Montgomery on February 4, 1861. After 1862 Union troops held the Tennessee Valley. One of the most important naval battles of the Civil War was won in Mobile Bay in 1864, but most of the state was unoccupied until 1865. Alabama ratified the 13th Amendment to the U.S. Constitution in 1865. However, Alabama refused to ratify the 14th Amendment in 1867 and it was at that time that Alabama was placed under military rule. The following year a new state legislature operated under a new constitution that approved the 14th Amendment and the military rule ended. Federal troops stayed in Alabama until 1876. African Americans continued to suffer oppression that continued for decades.
Alabama’s government was controlled by the carpetbaggers and scalawags during this reconstruction era and corruption was widespread. During this time the mining of coal and iron was expanded giving rise to industry in Alabama.