Monson returned to the diplomatic service in 1869, being appointed Consul in the Azores in 1869,[4] Consul-General in Budapest in 1871[5] and Second Secretary in Vienna; and to other posts, including as a special envoy in Dalmatia and Montenegro in 1876–1877.
The two governments agreed, "whereas each of the parties hereto has entire confidence in the learning ability and impartiality of Sir Edmund Monson Her British Majesty's Envoy extraordinary and Minister plenipotentiary in Athens", to submit the dispute to his binding arbitration.
[10] Monson decided against the United States, but "so satisfied was this [U.S.] government with the judgement of Sir Edmund that it joined Denmark in presenting to him a service of silver plate".
On all sides regrets are expressed that an English diplomatic representative who is so thoroughly acquainted with Greek affairs, and who has gained the sympathy and confidence of all parties, should leave the country at this critical time.
[17] Monson felt that there might be other reasons for Dreyfus's conviction, but "there has been so much underhand villainy in the way of forgeries connected with the trial, the existence of which is not known to the fanatical and anti-Semitic public, that the government will doubtless be able if they are sufficiently unscrupulous, to produce confirmatory evidence".
[19] Monson added when Münster was asked about the French officer who was the real spy for Germany, Ferdinand Walsin Esterhazy, that "he replied with a significant smile 'Ah the other gentleman, we know him well.
On 14 October 1898, Monson reported to London that the French Army was considering a coup d'état against the government in response to its handling of both the Dreyfus Affair and the Fashoda crisis.
On 6 December Sir Edmund Monson delivered a speech to the British Chamber of Commerce in Paris including this passage: I would earnestly ask those who directly or indirectly, either as officials in power, or as unofficial exponents of public opinion, are responsible for the direction of the national policy, to discountenance and to abstain from the continuance of that policy of pin-pricks which, while it can only procure ephemeral gratification to a short-lived ministry, must inevitably perpetuate across the Channel an irritation which a high-spirited nation must eventually feel to be intolerable.
Such ill-considered provocation, to which I confidently trust no official countenance will be given, might well have the effect of converting that policy of forbearance from taking the full advantage of our recent victories and our present position, which has been enunciated by our highest authority, into the adoption of measures which, though they evidently find favour with no inconsiderable party in England, are not, I presume, the object at which French sentiment is aiming.
It was a discordant note in the harmony of the speech, and in the French rendering it was toned down with a compliment to M. Delcassé [the foreign minister], whose conciliatory attitude the Ambassador commended with gratitude.
"[24] However, although Monson's remarks caused a storm in the French press, it blew over and "was the last incident to disturb relations which were destined to assume, before his retirement from the Paris Embassy, a character of exceptional cordiality and confidence.
... Sir Edmund Monson contributed his own not inconsiderable share to the rapprochement between Great Britain and France which finally took shape in the agreements of April 4, 1904, and when he resigned, at the beginning of the following year, the entente cordiale ... was already firmly established.