A once top-secret document from Adolf Hitler surfaced in 2012 which details plans for an apparent invasion of Ireland and Scotland during World War II. It was part of  “Operation Sea Lion.”

Historians believe that the documents will prove surprising to the Irish who believed their neutrality could have kept them safe from attack during World War II.

Despite being officially neutral, Ireland allowed German U-Boats to operate in its waters.

The plot to invade Ireland, as part of  ‘Operation Sea Lion,’ is detailed in the German booklet that was held in secret since the conclusion of the war. The document is believed to have been handled by top-ranking Nazi officials.

The booklet includes eight fold-out maps that are marked with areas of interest for a Nazi invasion and proves that almost nowhere was off-limits in Ireland for invasion. Spots marked on the maps pinpointed dams, ports, cities, high ground and beaches in counties all around the country.

It is believed that Hitler called off Operation Sea Lion on September 17, 1940 after the Luftwaffe's failure to gain air supremacy over England during the Battle of Britain.

Historians who have analyzed the top-secret document agree that invading Ireland would have been a smart military move for the Nazis as it would have helped an invasion on Great Britain, and strained relations between Ireland and the United States.

The dossier went up for auction.

Richard Westwood Brookes, a historical documents expert at Mullocks Auctioneers, said, “This will come as quite a surprise as the Irish believed that the country's neutrality protected them from the Nazis.”

“They were clearly wrong and it is a very sobering reminder that no one in the world was safe from the evil of Hitler.

“Despite the fact that many Irish were sympathetic to Germany throughout the war, they were clearly earmarked by the Nais for invasion and for the same fate as all the other countries in Europe.”

Brookes added that “We have naturally come across invasion plans for Britain before but I have never seen one for Ireland.”

* Originally published in 2013.