On the day of the battle, the Union ironclads Essex and St Louis, transporting troops down the Mississippi in fog, engaged the Confederate cotton clad warships General Polk, Ivy and Jackson and the gun platform New Orleans at a curve known as Lucas Bend in Kentucky.

[4] The term timberclad is usually reserved for the Union ships Lexington, Tyler, and Conestoga which had heavy timber attached as 'armor'.

[6] Both ships were sent to Cairo, Illinois, early in the Civil War as part of troop transports moving the army into Tennessee.

[7] Cairo, at the confluence between the Mississippi and Ohio rivers, was a key supply point and headquarters for Flag Officer Andrew Hull Foote and General Ulysses S. Grant.

[4] The Confederate Ivy was launched in 1845 as a privately owned commercial vessel originally named Roger Williams, and later the El-Paraguay.

[9] The CSS Jackson was another privately owned vessel built in 1849 before being acquired in May 1861 by the Confederacy and commissioned into active service in June.

[4] On the evening of January 10 the Essex and the St Louis moved off in heavy fog from the ferry landings at Cairo in convoy escorting troop transports carrying Brigadier General John Alexander McClernand's brigade.

William Porter moving off-route to investigate two suspicious, but later revealed to be legitimate, boats moored on the riverside.

Thus, today, Lucas Bend consists of an area of Kentucky which lies on the "wrong side" of the present-day main course of the river.

Rodgers' original three warriors – now more often called the 'old wooden gunboats' – were regarded not as the major flotilla elements, but as supporting vessels to an expanding and more heavily armoured naval force.

"[4] After having reluctantly given up the chase, the Essex and the St Louis returned to Cairo to replenish and begin ammunition runs, and were relieved by two other vessels which took up guarding Fort Holt.

[2] In the days following, Porter used a buoy to float towards the Confederate positions a challenge: "Hollins: Why don't you accursed, cowardly rebels bring out your gunboats and fight us.

Confederate Captain Miller sent his reply in the same medium: "Sir: The ironclad steamer Grampus will meet the Essex at any point and time your Honor may appoint and show you that the power is in our hands.