Joseph Hackin was born in Luxembourg but raised in France and became a French citizen in 1912. He studied at the School of Oriental Languages and became assistant curator of the Guimet Museum in Paris. His studies of Archeology were cut short when Joseph was mobilized by the French Army in August 1914 and took part in the Battle of the Marne in the 74th Infantry Regiment. He continued to serve throughout the First World War, fighting at Verdun and later Serbia, raising to the rank of Lieutenant and being wounded three times. As officer of the Légion d'Honneur he returned to his civilian life in the Guimet Museum in June 1919 and was appointed as curator. Joseph continued his studies at the Ecole du Louvre, where he met Marie Parmentier who became his wife in 1928. Together they led several excavation campaigns in Afghanistan, particularly interested in the Great Buddha of Bamiyan.
Upon declaration of war in September 1939 Joseph Hackin returned to active duty as Captain of the Reserve and was posted to the Mediterranean in March 1940 after he requested to join a combat unit and was sent to Kabul and promoted to Colonel in May 1940. After the armistice the Vichy government asked him to take over their diplomatic representation in Afghanistan, but he refused and returned to London via Bombay to join the civil service of the Free French Forces together with his wife. They were sent back to India as representatives of General de Gaulle, but were lost on passage aboard Jonathan Holt from Liverpool to Takoradi.