"John I (February 1346 – 23 September 1390) was the Duke of Lorraine from 1346 to his death. As an infant of six months, he succeeded his father, Rudolph, who was killed in the Battle of Crécy. His mother was Mary, daughter of Guy I of Blois.
During his long minority, the regency was in the hands of his mother and Eberhard III of Württemberg. In December 1353, John did homage for the duchy to Charles IV, Holy Roman Emperor, who made him lieutenant-general of the Empire in the Moselle country. In 1354, John II of France granted him a dispensation to allow him to govern the duchy despite not yet being of age." - (en.wikipedia.org 31.01.2020)
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