[2][3] Leopold initially refused the offer, but on 21 June 1870, he accepted the Spanish crown and the name "Leopoldo I".

[4] Additional demands that were made by the French government heightened diplomatic tensions between Paris and Berlin.

The deliberate shortening of a diplomatic communiqué, the Ems Dispatch, led to declaration of war by France.

France lost most of Alsace and part of Lorraine and had to pay Prussia war reparations.

They had the following children: Had Leopold succeeded to the Spanish throne, he could possibly have founded a second German dynasty in Spain, following the extinction of the House of Austria less than two centuries earlier.