Adolf Mahr, a Nazi and Celtic archaeologist in the National Museum, was centrally involved in the selection of archaeological sites for excavation and was the main adviser to the Harvard Archaeological Mission. He came to Ireland from Austria in 1927 to take up a position as Keeper of Irish Antiquities at the National Museum of Ireland. He was a member of the Nazi Party and also head of the Auslandsorganisation, an organisation for Germans living abroad, described as ‘useful for propaganda and espionage activities’. Mahr was suspected of being a Nazi spy, ‘handily placed’ in the National Museum of Ireland. He was appointed director by de Valera in 1934 and was described by Frederick Boland, from the Department of External Affairs, as ‘the most active and fanatical national socialist in the German colony here’. Mahr had the title ‘professor’ conferred on him by Hitler in 1938 and subsequently worked for the Nazis, broadcasting propaganda on radio during the Second World War.