Okubo was one of the Iwakura Embassy which set out from Tokio at the close of 1871 and visited the United States of America, Great Britain, and the various countries of Europe, ostensibly to announce to the powers what sweeping changes had been effected in Japan from the date of the present ruler’s accession in 1867. The Embassy was headed by Prince Iwakura, and associated with him in addition to Okubo Toshimichi were Ito Hirobumi, Kido Takakoto, and Yamaguchi Naoyoshi. Only one leading member of that mission, the Marquis Ito, now survives. The especial aim of the ambassadors was to procure revision of the treaties with the Western nations which had been entered into by the Government of the Shogun, and under which compacts the position of Japan was considered to be that of a country under the tutelage of America and the European States. There was, however, a duty imposed upon the Mission that was of far greater importance to the future of the Japanese nation even than those already specified, for it was entrusted with the task of collecting information in all quarters regarding foreign institutions, methods of government, laws and their enforcement, and of gathering at first hand every detail needful to the adaptation of the systems of the Occident to the requirements of the Far East. Although at that time a revision of the treaties proved to be impossible of attainment, the mission was in other respects of immense service to Japan, and Okubo, for one, became as fully convinced by what he saw in the West of the advantages of representative government as were those among his colleagues who had previously seen something of its results. Ito, for example, had been to this country before, and so had Hayashi Tadasu, as he then was, the Secretary to the Mission, who had studied for some time in a private college in England. The work of the embassy was most conscientiously carried out, and its members journeyed here and there in search of opportunities to add to their stock of knowledge on every point that conceivably might be of value to the departments of State with which they were for the most part individually as well as collectively identified. In the new administration at Tokio, immediately on the mission’s return, Kido was entrusted with the portfolio of Home Affairs, Ito Hirobumi became Minister of Public Works, and Okubo received the appointment of Gaimukiyo, or Minister for Foreign Affairs. One effect of the visit of the Japanese Ambassadors to the European capitals was speedily visible in the withdrawal of the garrison of British troops which had for years been maintained at Yokohama, the ability of the Imperial Government to protect the foreign residents at the ports opened by treaty to foreign trade having been demonstrated to the satisfaction of the British Government, and the last of the guard of marines which had been quartered on the Bluff in Yokohama took their departure early in 1873.