He was envoy extraordinary to Venice from 1674 to 1679.
In 1909 he became envoy extraordinary and minister plenipotentiary to Guatemala.
Layard resigned from office in 1869, on being sent as envoy extraordinary to Madrid.
From 1693 to 1703 he was Envoy Extraordinary to Hanover.
In the following year he was appointed Envoy Extraordinary to Spain.
From 1838 to 1850 he was envoy extraordinary and minister plenipotentiary in Stockholm where he died.
In 1894, d'Anethan was promoted to the rank of envoy extraordinary and minister plenipotentiary.
He resumed his career on 28 April 1851 as envoy extraordinary and minister plenipotentiary at Lisbon.
During his stay in London the pope named him a full auditor, and in 1795 gave him additional powers as envoy extraordinary.
In September 1713 he was appointed Envoy Extraordinary to France, but did not take up the post.