March 7/8 - Battle of Pea Ridge (Arkansas), also known as Elkhorn Tavern, is a Union victory and helps keep Missouri a Union State.

 From the March 29, 1862 edition of Harper’s Weekly

THE BATTLE OF PEA RIDGE.

WE devote page 196 to an illustration of the great battle won by General Curtis at PEA RIDGE, ARKANSAS, on 6th, 7th, and 8th March. The official report of General Curtis is as follows:

HEAD-QUARTERS, ARMY OF THE SOUTHWEST,

PEA RIDGE, ARKANSAS, March 9, 1861.

GENERAL,—On Thursday, the 6th inst., the enemy commenced an attack on my right wing, assailing and following the rear-guard of a detachment under General Siegel to my main lines on Sugar Creek Hollow, but ceased firing when he met my reinforcements about four P. M.

During the night I became convinced that he had moved on so as to attack my right or rear, therefore early on the 7th I ordered a change of front to the right, my right, which thus became my left, still resting on Sugar Creek Hollow. This brought my line across Pea Ridge, with my new right resting on Head Cross Timber Hollow, which is the head of Big Sugar Creek. I also ordered an immediate advance of the cavalry and light artillery, under Colonel Osterhaus, with orders to attack and break what I supposed would be the reinforced line of the enemy. This movement was in progress when the enemy, at eleven A. M., commenced an attack on my right. The fight continued mainly at these points during the day, the enemy having gained the point held by the command of Colonel Carr, at Cross Timber Hollow, but was entirely repulsed, with the fall of the commander, McCulloch, in the centre,

Full article 

Battle of Pea Ridge
THE BATTLE OF PEA RIDGE, ARKANSAS-THE FINAL ADVANCE OF OUR TROOPS, MARCH 8, 1862.-[SEE PAGE 202.]

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