Naval battles of the American Civil War The naval engagements of the American Civil War changed the foundations of naval warfare due to the first - time use of ironclad s and submarine s , and the introduction of newer and more powerful naval artillery . The first shots of the naval war were fired on April 13 , 1861 , during the Battle of Fort Sumter , by the Revenue Service cutter USRC " Harriet Lane " and the final on June 22 , 1865 , by the Confederate raider CSS " Shenandoah " , in the Bering Strait , more than two months after General Robert E . Lee ' s surrender of the Confederate Army . Introduction . The Naval Battles of the American Civil War not only happened out at sea , but also in major rivers of the United States . Without the naval battles that occurred during this war , the outcome could have been reversed . The naval force of each army also provided the ground troops with supplies and medical care to carry out the war as planned . Both ground troops and naval troops had to work together in the Civil War in order for them to succeed . Naval Purpose . The battles that occurred in the water played a major role in helping the troops that were marching all over the country . The navies of the Union and Confederates not only fought against each other but also served primarily as transportation of foot troops and supplies . This is why each navy battled against each other . Without a navy , either the Union or the Confederate armies could not get the supplies and man power that they needed to successfully carry out the war . The ships also served a very important purpose for their armies . The Civil War had a great number of casualties . Therefore , the naval ships served as floating hospitals for the soldiers that had been injured . Blockades also played a huge role in the defeat of the Confederate military . Naval Blockades kept the south from trading and gaining supplies for their soldiers , which caused them to have to surrender to the Union . Supply running was one of the biggest parts that the Navy played during the American Civil War . If either the confederates or the union did not receive the supplies that they needed , then they would suffer more and more until they would receive it . The major strategy that the union took in the civil war was blockading southern ports . This would not allow the south to get help from any other countries via shipping ports . There would be no food , water , ammunition , guns , clothes , or medical supplies for them . Now , this strategy was not effective right away . The south still had a lot of supplies with them before the blockading started . The union had to hold off the south for a while until they would eventually run out of supplies and surrender . This was tough for the union because of several things . One , since the south kept fighting during the blockading , the union received more casualties and deaths . Two , this made the war last longer than was expected . Eventually , the confederate army could not hang on much longer and surrendered and the feet of the union . Hospitals were very much needed during the civil war as well . There were so many injuries that occurred that soldiers were in desperate need of medical attention . The naval ships were secondarily used as floating hospitals for soldiers . Both the confederates and the union used this tactic . It helped out the armies because the more room they had for medical use the better off they would be . Naval Battles . One of the most important and famous naval battles of the Civil War was the clash of the ironclads , between the USS Monitor and the CSS Virginia . The battle took place on March 9 , 1862 . The battle lasted for a several hours and resulted in a tactical draw . Both ships were very well protected by thick armor plating , which prevented any lasting damage to either ship . Another great naval battle that did not end well for the Union was in Charleston , South Carolina , in 1865 . This battle was very poorly carried out by the north . This is when the Union was sent to attack the Confederate army from sea to land . The confederates held off the Union and made them retreat during this battle . Admiral Du Pont was sent with 9 ironclads to attack Charleston . When he was given the news , he did not expect to come out victorious from this battle . He would have to steer his ships up the fort and stand still in order to attack Charleston . This gave the Confederates a valuable edge on the Union . The Union Naval Force was so vulnerable during this battle that within two hours they were forced to retreat from the attack in order to not receive too many casualties in one single battle . The result of this failed battle was that the Union would be blockaded for two more years . Also , the south had set up several forts alone the coast of South Carolina where they could easily attack the Union . The sinking of the C . S . S . Alabama by the U . S . S Kearsarge was an intense naval battle that ended in the sinking of one of the best Confederate ships in its fleet . The CSS Alabama fired the first shot . Soon after the U . S . S . Kearsarge shot back . Both of the ships had their main weapons and cannons on their starboard side ( right side ) , therefore , both ships were fighting in a circular pattern . The U . S . S . Kearsarge was slightly faster , had more fire power , and a bigger crew than the C . S . S . Alabama . This gave the Union an advantage in this naval battle . The confederate ship had taken many shots and casualties and eventually began to sink . Once the south realized that they were slowly leaking , they tried to run back to shore . They did not make it very far . The water started rising quickly and shut off their engines . When this happened , the confederates had no other choice but to surrender . The remaining survivors were rescued by the U . S . S . Kearsarge . This was an important battle for the Union since it was towards the end of the Civil War .