Final answer:
The Confederate ironclad used in an attempt to break the Union's naval blockade during the Civil War was the CSS Virginia.
Step-by-step explanation:
The Confederates made a bold attempt to break the blockade with an Ironclad warship named the CSS Virginia. During the American Civil War, the Confederacy sought to circumvent the Union's naval blockade, which had significant impacts on the Southern economy and war effort.
The Confederacy hoped to leverage Britain's need for cotton and its technological advancements in building ironclad ships. They aimed to utilize these armored warships to challenge the Union blockade, purchasing vessels like the CSS Alabama and CSS Florida. However, the iconic ironclad that the question likely refers to was the CSS Virginia, famously known for its clash with the Union's USS Monitor in the Battle of Hampton Roads, a landmark naval battle in the history of warship design.