PRESIDENT’S WAR ORDER, £ EXECUTIVE MANSION,

No. S. ) Washington, March 11, 18C2.

Major General McClellan having personally taken the field at the head of the Army of the Potomac until otherwise ordered, he is relieved from the command of the other military departments, he retaining command of the Department of the Potomac.

Ordered, further, That the two departments now under the respective commands of Generals Halleck and Hunter, togelher with so much of that under General Buell as lies west of a north and south line indefi¬ nitely drawn through Knoxville, Tennessee, he consolidated and desig¬ nated the Department of the Mississippi, and that, until otherwise ordered, Major General Halleck have command of said department.

Ordered, also, That the country west of the Department of the Poto¬ mac and east of the Department of the Mississippi, be a Military Department, to he called the Mountain Department, and that the same be commanded hy Major General Frhmont.

That all the Commanders of Departments, after the receipt of this order by them respectively, report severally and directly to the Secretary of War, and that prompt, full, and frequent reports will be expected of all and each of them.

ABRAHAM LINCOLN.

By order of the Secretary of War:

L. THOMAS,

Adjutant General.

Official :

Assistant Adjutant General.