By Mark Abrams

PHILADELPHIA (CBS) – While many historians concur the bombardment on Fort Sumter triggered the start of the Civil War, there is a document President Abraham Lincoln signed just days after the event that is actually considered the legal launch of the bloody conflict between the states.

It was April 19, 1861 – seven days after the Confederates let loose an artillery barrage on Fort Sumter in South Carolina.

It was on that date that President Abraham Lincoln signed a document ordering Union Navy blockades of Confederate ports.

“So, if you blockade the ports of your own country, you’re technically declaring war against your own country, which has certain constitutional implications. It took a true leader like Lincoln to recognize how important this was and that it had absolutely had to be done.”

Nathan Raab, vice president of the Raab Collection here in Philadelphia, is selling that original, one-page document for a private collector. And, the asking price is $900,000.

“At the end of the war, the Supreme Court, in fixing the beginning of the war, found this to be the start date of the Civil War. So this document, the order to blockade the Confederacy, was, itself, the beginning of the Civil War.”

He says it is a significant piece of Civil War history that has been displayed in museums over the years, including the National Constitution Center here in Philadelphia.

And, he says, it likely will be released again in the years ahead for public view by the new owner.

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