The Duke of Marlborough paid him well for information on the intrigues of Louis XIV at the court of Saxony.
Robethon also worked to assist Marlborough in neutralising Charles XII of Sweden, and undermining overtures Louis made to the allies in 1707.
Worldly, adept and well briefed on English politicians, Robethon had influence with George I, though not with the ladies of the court.
[1] Robethon made the first French translation of Alexander Pope's An Essay on Criticism (in verse), which was published in Amsterdam and London in 1717.
[1] Some of Robethon's correspondence was in 11 volumes of Hanoverian letters with the Stowe MSS., now in the British Library.
The collection was formed around the Electress Sophia's papers, which were entrusted to Robethon by George I on his mother's death in 1714.
They were later sold by the executors of the secretary's son, Colonel Robethon, in 1752, to Matthew Duane, and while in his hands were seen by James Macpherson.