[SunkenCiv]

It was passed during the Buchanan administration, when the proslavery and eventual secessionists were still in Congress, but never ratified. Lincoln never endorsed it, and it didn’t get ratified. It also wouldn’t have been enough, as experience proves.

http://cwcrossroads.wordpress.com/2011/01/24/lincoln-and-the-corwin-amendment/

[Sherman Logan]

It was passed during the Buchanan administration, when the proslavery and eventual secessionists were still in Congress

Only partially correct.

The Deep South states had already all seceded, although all the Upper South and Border states were still sitting in Congress.

It was ratified by OH and MD, and perhaps by IL.