On 26 July 1850 Antoine and Arnaud received the gold medal of the
Société de Géographie. On September 27, 1850, the two brothers were made
knights of the Legion of Honor.
Return to Ethiopia Arnaud returned to France with a clear objective: the realization of his ambitious project to reconstruct the ancient Christian empire of Ethiopia, with Dejazmach Goshu as its leader. He presented his proposal to the French government through the
Duke of Bassano. The response was favorable, and although Arnaud was not granted an official diplomatic mission, he was entrusted with delivering gifts to Dejazmach Goshu on behalf of France to foster an alliance. However, honoring a request from his mother, Arnaud pledged not to cross the
Tekezé River—a tributary of the Black Nile located along the western border of Tigray—so that he could maintain an accessible route to the sea for his return to France. Unfortunately, Goshu was located on the opposite side of the Tekezé, in Gojjam, making it impossible for Arnaud to meet him without breaking his promise. Despite this limitation, Arnaud and Goshu maintained a prolific correspondence, exchanging numerous letters. Arnaud, however, remained resolutely committed to his oath and refrained from crossing the river. In November 1852, the
Battle of Gur Amba ended with the death of Dejazmach Goshu and the triumph of Kassa Hailu, who would later come to power as Emperor
Tewodros II. For Arnaud, this event was a devastating blow. He had not only lost a close friend but also seen his hopes of restoring a Christian empire in Ethiopia extinguished. Overwhelmed by despair, he returned to France at the end of December 1852. Arnaud’s final attempt to strengthen ties between France and Ethiopia took place during the 1860s, a period marked by escalating tensions in the region. The British had established a formidable presence in Sudan, Aden, and Somalia, heightening the likelihood of a confrontation with Emperor Tewodros II of Ethiopia. Recognizing the strategic importance of Ethiopia, Arnaud sought an audience with
Napoleon III to advocate for French involvement. He presented a case highlighting the potential benefits France could offer Ethiopia and the advantages of a Franco-Ethiopian alliance. Although Napoleon III received Arnaud courteously and listened attentively, he ultimately declined to take action, citing France’s obligations under existing alliances with England. Arnaud’s hopes of fostering cooperation were thus thwarted. In 1868,
a British military expedition was launched against Ethiopia, culminating in the tragic conclusion of Emperor Tewodros II’s reign with his suicide.
Second marriage and children Arnaud married Elisabeth West Young, an American and the daughter of Robert West Young (1805–1880), a physician, and Anne Porter Webb. They had nine children: • Anne Elisabeth (1865–1918); • Michel Robert (1866–1900); • Thérèse (1867–1945); • Ferdinand Guilhem (1870–1915) • Marie-Angèle (1871–1955); • Camille Arnauld (1873–1968); • Jéhan Augustin (1874–1912); • Martial (1878–1914); • Marc Antoine (1883–1914). In Paris, Arnaud hosted a salon at his residence on the rue de Grenelle, which became a regular meeting place for intellectual and educated individuals. Despite the prestige associated with such gatherings, Arnaud held a deep aversion to worldliness and ultimately decided to leave Paris. Seeking a quieter life, he relocated with his family to the Basque Country, where he commissioned the construction of the château of Elhorriaga in
Ciboure. The castle was designed by the architect Lucien Cottet. During the
Second World War, the castle was requisitioned and occupied by the
Wehrmacht. It was demolished in 1985 to make way for a real estate development project.{{cite book
Life in Ciboure and death In Ciboure he quickly gained a reputation as a charitable man, but always remained discreet. The first volume of the account of travels in Ethiopia was published by Arnauld in 1868 under the title
Twelve years in Upper Ethiopia. It recounts the period 1837–1841. The next three volumes were not published during his lifetime. Volume 1 was translated for the first time in 2016 into the
Amharic language, Volume 2 in 2020 and volume 3 in 2025 under the title "በኢትዮጵያ ከፍተኛ ተራሮች ቆይታዬ" (
My stay in the high mountains of Ethiopia). Arnaud died on 8 November 1893; he is buried in the cemetery of Ciboure. The photograph in Ethiopian clothes was taken shortly before his death. The memory of "Ras Mikael" remained alive in Ethiopia for a long time, indeed Emperor
Menelik II referred to him: ==Publications on Ethiopia==