Francis was born on 23 November 1508 in Uelzen. His father, Henry the Middle (1468-1532), had planned that Francis would later become the Bishop of Hildesheim, but that proved impossible due to the worsened political situation.
After his father (who had supported a losing French contender for the imperial elections) was exiled to Paris in 1521, his two elder brothers, Otto and Ernest the Confessor, ruled the severely indebted Duchy of Celle.
They arranged for their brother, Francis, who was too young to share power, to have a professional education and, at the age of 16, sent him to the University of Wittenberg. When he came of age in 1526, he spent another ten yearsat the court of the Electorate of Saxony.
There he was impressed by the extravagant courtly life at the royal court with its feasting, hunting and travelling. Not until 1536 did he return to Celle at the prompting of his elder brother, Ernest, who had since espoused the Lutheran doctrine.