Claim: John James Heidegger went to England in 1708 to be a Swiss negotiator, which he was not successful at; he became a prviate in the Guards, and was influential in management of the opera.
Evidence: The son of Zürich clergyman Johann Heinrich Heidegger, Johann Jacob Heidegger came to England in 1708 as a Swiss negotiator. He failed in his undertaking, and was involved in difficulties. So he entered as a private in the Guards, and afterwards became influential in the management of the opera.