Antoine Thomson d'Abbadie d'Arrast (3 January 1810 – 19 March 1897)[1] was a French explorer, geographer, ethnologist, linguist and astronomer of Irish birth, renowned for his expeditions in Ethiopia[nb 1] during the early 19th century.

[2] Antoine Thomson d’Abbadie was born a British subject in Dublin, Ireland, to a family of partial Basque noble descent from the French province of Soule.

“After completing college in 1829,” he later recounted, “I undertook six years of study specifically aimed at preparing myself for the exploration of Africa’s interior, which I intended to enter through Tunisia and Morocco.

Reading the travels of Bruce transported my imagination to East Africa—a region marked by extensive migrations and the origins of enduring traditions, yet veiled in mystery.

I became convinced that the most noble pursuit a man could dedicate himself to was the study of his fellow human beings.” During these six formative years, d’Abbadie rigorously prepared himself for the challenges of exploration.

He became skilled in fencing, practiced gymnastics, competed in endurance races under various weather conditions, and developed into an accomplished swimmer.

The findings of this expedition were later published in 1873[1][nb 3] under the title Observations relatives à la physique du globe faites au Brésil et en Éthiopie.

Reflecting on his time in Ethiopia, he remarked, "When residing in a foreign country without any known antecedents, it is advisable to adopt a vocation in line with local customs, as failure to do so may result in being branded as a political spy, a hazardous accusation in any nation.

As I was unable to engage in combat, agriculture, or merchandising, I identified as a "mamhir", or teacher and scholar, during my time in Christian Ethiopia and received an education from their public and non-compulsory schools."

They exchanged their European attire for the turban and toga of the Ethiopians and traversed the region barefoot, as, at the time, only lepers and Jews wore sandals.

[6] The d’Abbadie brothers undertook extensive journeys throughout Ethiopia, meticulously documenting a wide range of topics, including human and physical geography, religion, legislative texts, ethnography, philology, linguistics, numismatics, and history.

By late 1848, after fulfilling and exceeding their ambitious self-imposed goals, the d’Abbadie brothers departed Ethiopia, leaving behind a legacy of unparalleled scholarly and cultural contributions.

But time and the investigations of subsequent explorers have shown that Abbadie was quite trustworthy as to his facts, though wrong in his assertion — hotly contested by Beke — that the Blue Nile was the main stream.

The topographical results of his explorations were published in Paris between 1860 and 1873[1] in Géodésie d'Éthiopie, full of the most valuable information and illustrated by ten maps.

[1][8] He also compiled various vocabularies, including a Dictionnaire de la langue amariñña (Paris, 1881), and prepared an edition of the Shepherd of Hermas, with the Latin version, in 1860.

The general account of the travels of the two brothers was published by Arnaud in 1868 under the title of Douze ans de séjour dans la Haute Ethiopie.

The popularity of the motto Zazpiak Bat is attributed to Abbadie, coined in the framework of the Lore Jokoak Basque festivals that he fostered.

The château still belongs to the Academy of Science to which it was bequeathed in 1895 on condition of its producing a catalogue of half-a-million stars within fifty years' time,[7] with the work to be carried out by members of religious orders.