USS Alfred Robb

Gwin placed a crew of 11 men on the prize and renamed her Lady Foote to honor Flag Officer Andrew H. Foote — who then commanded the Western Flotilla of which Tyler was a part — and his wife. However, Foote found this action embarrassing and directed Gwin to restore the vessel's original name.

Since the Confederacy still held much of the Mississippi River, it was impossible to send Alfred Robb to any Federal court then hearing admiralty cases. Hence, after the prize descended the Tennessee and Ohio Rivers to Cairo, Illinois, she was fitted out there for service in the Western Flotilla without prior adjudication. Upon the completion of her conversion to a so-called "tin-clad" gunboat, Alfred Robb began her Union service early in June 1862.

Apparently not commissioned, Alfred Robb — thereafter usually called simply Robb — departed Cairo on the night of 3–4 June; proceeded up the Ohio River to Paducah, Kentucky; and ascended the Tennessee River to Pittsburgh Landing where, two months before, Union gunboats had supported the river flank of Major General Ulysses S. Grant's embattled army, changing a highly probable defeat into a Union victory known to history as the battle of Shiloh.

Meanwhile, the powerful concentration of Federal forces which had prevailed at Shiloh moved south and captured Corinth, Mississippi. It then split, with General Grant pushing toward Vicksburg along a path roughly parallel to the Mississippi River while General Don Carlos Buell's troops turned eastward in the general direction of Chattanooga, Tennessee.

To check the advance of these Union forces which were penetrating deep into the Confederate heartland, defenders of the South struck back with guerrilla attacks, cavalry raids, and prolonged counter thrusts by whole armies. All these measures were designed to sever Northern lines of communication and supply. Union railroads, overland convoys of wagons, and supply ships quickly became favorite Confederate targets; and the importance of maintaining Union control of the rivers grew apace to assure Federal troops a steady flow of supplies and munitions.

Responsibility for keeping the Ohio River and its tributaries safe for waterborne Union logistics was placed on the gunboats of the Western Flotilla. On 20 August 1862, the commanding officer of that organization, Commodore Charles Henry Davis — recognizing that ". . . the gunboat service of the upper rivers had suddenly acquired a new importance" — charged Commander Alexander M. Pennock, his fleet captain and the commanding officer of the Union naval station at Cairo, Illinois, with taking these small warships under his ". . . special care . . ." with Lt. LeRoy Fitch in immediate command.

Since she was already operating in this area, Alfred Robb was one of Fitch's gunboats; and — except for occasional brief assignments on the Mississippi River — she served on the upper rivers through the end of the Civil War. One of the highlights of her service occurred on the night of 3 February 1863 when she joined several other Union warships in beating off a fierce attack by some 4,500 Confederate troops against the small Federal garrison in Fort Donelson, Tennessee.

She again entered the limelight on 19 June when a landing party from her engaged a Confederate force of some 400 soldiers. Robb's commanding officer estimated that the Confederates lost about 50 men, killed or wounded, while his ship suffered the loss of only one man killed and two wounded.