Since 1717 he commanded his own cuirassier regiment. In 1732 he became Governor of Sicily (the island was for a short time a part of Habsburg realm). On 28 November 1739 he was made a Knight in the Order of the Golden Fleece. In 1741 he attained the rank of field marshal.
In 1745 composer Christoph Willibald Gluck accepted an invitation to become house composer at London's King's Theatre, travelling to England, possibly in the company of Georg Christian but more likely with his younger cousin, Ferdinand Philipp, 6th Prince Lobkowicz.
Family
Johann Georg Christian married Countess Henriette of Waldstein-Wartenburg in Prague on 11 March 1717. They had 10 children. Two of their sons were killed in battle; two other sons, Joseph Maria Karl and August Joseph Anton, served in the Austrian military and diplomatic corps and became Knights in the Order of the Golden Fleece and one, Ferdinand Maria of Lobkowicz, became bishop of Ghent.
Kasík, Stanislav; Mašek, Petr; Mžyková, Marie (2002). Lobkowiczové: dějiny a genealogie rodu [Lobkowiczs: A History and Genealogy of the Family] (in Czech) (Historia nobilium ed.). Olomouc: Matice cyrilometodějská. ISBN80-903040-3-6.