Earliest possible implementation of the Anaconda Plan and subsequent effects

So how early on could Lincoln and his generals have agreed to it, and how soon would they be able to end the war as a result? Would the Emancipation Proclamation still be declared and all black military units raised if the war had been ended sooner?
 

Anaxagoras

Banned
They pretty much implemented the Anaconda Plan from the get-go IOTL. As soon as the First Battle of Bull Run made it clear that the war was not going to be over with a quick capture of Richmond, the navy began serious efforts to blockade the South and the armies and river gunboat flotillas began operations in the West to seize control of the Mississippi Valley. I really see no scenario in which it might have been implemented sooner.
 
The one difference between this and OTL is that if this is a deliberate plan then the Army of the Cumberland may wind up smaller and assigned a defensive role and the Army of the Tennessee expanded in size. This only changes some of the details, not the overall picture, as Henry Halleck will still fumble in this theater and this will still give the CSA quite some time to fight a war in the Mississippi River region.
 
Prevent the rise of George McClellan.

The Anaconda Plan specifically included a drive down the Mississippi to split the CSA in two. McClellan's strategy as put forth in his April 27, 1861 letter to Scott involved a direct drive on Richmond. McClellan felt the Mississippi should be ignored in favor of operations on the Tennessee.

And there's McClellan's part in the ouster of Scott.
 
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