O'Conor entered the diplomatic service in 1866. In his early years, he was attached to the Embassy in Berlin, achieving the rank of Third Secretary in 1870. He served as Secretary at the Hague, Madrid, Rio de Janeiro, and Paris. He was trained in the diplomatic service by
Richard Lyons, 1st Viscount Lyons, and was a member of the
Tory-sympathetic 'Lyons School' of British diplomacy. He was Secretary and Chargé d'Affaires at Peking and Washington, Political Agent and Consul-General in Bulgaria.
Head of Mission O'Conor's first ministerial appointment was at the British Legation at Peking. • 1895: In St. Petersburg, he was Ambassador of His Britannic Majesty in the Imperial court of the Russian Czar. • 1898: In Constantinople, he was Ambassador to the Court of the
Sublime Porte of the Ottoman Empire. ==Family==