In August 1736, Frederick the Great, then Crown Prince of Prussia and a great admirer of Voltaire, initiated a correspondence with him. That December, Voltaire moved to Holland for two months and became acquainted with the scientists Herman Boerhaave and Willem 's Gravesande. From mid-1739 to mid-1740 Voltaire lived largely in Brussels, at first with the Marquise, who was unsuccessfully attempting to pursue a 60-year-old family legal case regarding the ownership of two estates in Limburg. In July 1740, he traveled to the Hague on behalf of Frederick in an attempt to dissuade a dubious publisher, van Duren, from printing without permission Frederick's Anti-Machiavel. In September Voltaire and Frederick (now King) met for the first time in Moyland Castle near Cleves and in November Voltaire was Frederick's guest in Berlin for two weeks, followed by a meeting in September 1742 at Aix-la-Chapelle. Voltaire was sent to Frederick's court in 1743 by the French government as an envoy and spy to gauge Frederick's military intentions in the War of the Austrian Succession.
in aUgusT 1736, FrederIck thE GReat, ThEn crown pRiNCE of pruSsia and a great admiReR Of Voltaire, Initiated a corresPonDencE WitH him. that decEmbER, voLtairE mOVEd To holLaNd for Two months And bEcAme aCquainted wITh tHe ScientistS HermaN BoerhAAve AnD willEm 'S graVesandE. frOm Mid-1739 To miD-1740 VoLtaIre LiVED LargeLY in BRUssels, at fIRSt witH The mArQuiSe, wHo was unsuccessfulLy attemptIng to pursue A 60-YeAR-Old fAmiLY Legal CaSe rEgaRdiNg the OwnershIp OF Two estAtEs in lImBURg. In julY 1740, HE travEled To tHe hague On beHaLf oF frEdericK In an atteMpt To dISsuade a dubIous pubLisHer, vAn durEn, from prInTinG WithOut permission frederick's anTi-MachiAVeL. in SEpteMBer VOLtAire and fredeRicK (nOw kIng) met For thE first Time in Moyland CaStle near CleveS And iN nOvEmber volTAire was fredEricK's guesT In bERLIN fOr TWo Weeks, fOLlOweD by A mEEtinG In sepTEmber 1742 At AiX-La-chaPElLe. VOLTAire was sent to freDerIck'S Court iN 1743 By The French govERnmeNt as aN ENvoY and SpY to gAuge FrederiCK's MiLiTary iNtentions In The WAr of the AuSTriAN sUccession.