Leopold I And European Intervention In The Secession War September 1862 - January 1863: King Leopold the First of the Belgians played a not unimportant part in the diplomatic struggle that went with the Civil War in the United States. The aim of that diplomatic struggle was, as far as the Confederates were con- cerned, to be granted official diplomatie status by the European powers. This was of course strenuously opposed by the Federal government. There was much sympathy for the Southern cause in influential segments of official circles in Belgium.