Final answer:
In April 1862, Commander David Farragut successfully led the Union navy to secure New Orleans, a critical Confederate port during the Civil War.
Step-by-step explanation:
In the spring and summer of 1862, during the American Civil War, Commander David Farragut was instrumental in securing control over a critical part of the Mississippi River for the Union. In a significant naval operation, Farragut led a fleet past forts guarding New Orleans and eventually secured the city in April 1862. This victory was pivotal as New Orleans was the most important port in the Confederacy at that time. The Union's success in New Orleans effectively cut off the Confederacy's access to the river and was a major strategic win in the war.