Diego de Castro was born in Pirano (Istria) on the 19^th August 1907, descending from a family that lived in Castrum Pyrrhanense for over one thousand years. Traces of the founder of the family, Venerio de Augusto de Castro Pirano, can be found in official documents dated 933, but a historical-genealogical reconstruction begins with Ottaviano de Castro from Pirano d'Istria, born in 1430.
De Castro attends the first years of the primary school in Pirano. Later his family moves to Salvore and later to Trieste where he obtains his High School certificate in 1925. Besides this cultural background, he already has an important store of memories and experiences, sometimes difficult and even tragical, concerning the years he spent at Salvore and then in Trieste. Salvore was one of the most important strategical points on the Italian-Austrian front during the first world war.
He matriculates in Rome at the Faculty of Law. In 1927 he publishes his first scientific work in the "Bollettino dell'Istituto statistico-economico" of Trieste University (L'attrazione matrimoniale tra individui di uguale religione a Trieste. 1904-1925). He graduates in 1929 with first class honours, discussing a thesis about the theoretic formulation of criminal-judicial statistics, that was published as XXIV volume of the "Annali di Statistica". Then he takes part in a competition at the University of Rome and becomes the assistant of Professor Rodolfo Benini for economic subjects and with statistic. In the meantime he attends courses at the School of Statistics (The Faculty of Statistics did not exist yet). In 1931 he qualifies free for statistic university teaching and on 16^th November of the same year he becomes official professor in the Faculty of Law at the University of Messina. Then he teaches for a year at the University of Naples. At the same time he becomes the Consultant for economic services of the industrial workers' Confederation in Rome; he will carry on this task till 1943.
From 1932 to 1935 he teaches also at the Superior Institute of Economic and Commercial Sciences of Turin (that later became the Faculty of Economy and Commerce) and in the mean time at the Faculty of Law of the same town. In 1936 he becomes full Professor of Statistics at the Faculty of Economy and Commerce of Turin, where he will teach also Demography. In that Faculty, in 1938, he founds the Institute of Statistics which, he directs till 1972. This institute, with the setting up of departments, has recently become "Diego de Castro Department of Statistics and Mathematics applied to human sciences".
His name is therefore still present in that historical palace in Piazza Arbarello, but above all in the minds of those who, in those lecture-halls, and not only there, could listen to his lessons in which he showed the intellectual curiosity that was one of the great gifts of his intelligence.
After teaching in Turin for 37 years, he moves to Rome at the Faculty of Economy and Commerce. He will teach Statistics and Demography in that Faculty for 12 years more. He reaches retirement age in 1982 after 50 years of didactic and scientific activity. In 1983 the President of the Italian Republic Sandro Pertini appoints him " Professor Emeritus".
At the end of the 30's, his constant commitment in the scientific research and in the didactics make him become a member of the Economic-Demographic and Statistic Italian Society of which he was also President. He was Vice-President of the Italian Institute of Anthropology. In 1946 he was appointed Fellow of the Royal Statistical Society in London; later he becomes an honorary member of the Italian Society of Statistics and of the Institute for the History of the Italian Risorgimento; he is also a member for life of the International Institute of Statistics.
From 1927 to 1997 he published many works in the field of demographic, economic, social, docimologic, syndacal and judicial statistics. He has been interested in this last field since 1934, when he wrote Metodi per calcolare gli indici di criminalità, that was judged by the Department of criminology, of the University of Philadelphia, the best work available at the moment and from the XIX century. In this field he was considered the most expert Italian student of legal statistics, of criminality and of criminology.
From 1941 to 1981 he contributed to the newspaper "La Stampa" of Turin with about 400 articles. In the first years after the war he contributed also to "Il Giornale di Trieste" and since 1952 he his contributing to "Il Piccolo" of Trieste.

Though strongly attached to the University, all through his life de Castro has also devoted himself to a diplomatic activity, that starts when he is obliged to interrupt his scientific and didactic activity owing to the war.
In the spring of 1941 he is called up for military service. Since he had not previously served in the Army, because he was the only son of a widow mother, he can choose the arm he wants to join. He joins The Navy as a Lieutenant in the Service Corps. He remained for four months in the Department of the Navy. He was then appointed as a member of the Interministerial Administrative office of prices. Later on de Castro is involved in the politically-military events of the country.
About the end of 1943 he becomes a member of the "Comitato Giuliano" of Rome and goes back to the Navy Ministry. In 1946 the Italian Government entrusts him with tasks concerning the preparation of the peace treaty. He is sent to England and to the United States. From July 1952 to April 1954 he is also the diplomatic representative of Italy with the Allied Military Government in Trieste and the political Counsellor of the Officer Commanding the Anglo-American Zone - General John Winterton. For Austria, Italy Yugoslavia and Slovenia these are decisive years, owing to the problem of defining their borders after the second world war. De Castro can be considered a protagonist of one of the most interesting and disputed pages of our times and one of the greatest experts of the problems concerning the Italian eastern borders. He knows very well the feelings, the reactions, the hopes, the illusion of the Italians of Trieste, of Istria and of the whole of Italy.For Austria, Italy Yugoslavia and Slovenia these are decisive years, owing to the problem of defining their borders after the second world war. De Castro can be considered a protagonist of one of the most interesting and disputed pages of our times and one of the greatest experts of the problems concerning the Italian eastern borders. He knows very well the feelings, the reactions, the hopes, the illusion of the Italians of Trieste, of Istria and of the whole of Italy.
De Castro wrote on these problems five books and many articles in newspapers and magazines. In particular two books are the most complete and detailed descriptions about the Italian political and diplomatic action from 1943 to 1954: Il problema di Trieste. Genesi e sviluppi della questione giuliana in relazione agli avvenimenti internazionali (1943-1952) published in 1953 and La questione di Trieste. L'azione politica e diplomatica italiana dal 1943 al 1954, published in 1981. In this last book he cleverly blends anecdotes, reflections and faithful reconstructions of crucial events - especially concerning the 40's and the 50's, the period of the so-called "Trieste problem". Thanks to his long and rich personal experience he can recall a century of difficult and controversial events, especially for Trieste and Istria, countries deeply involved in the first and second world war. He has always shown for these countries an impassioned commitment both as a diplomat and as a historian.
De Castro has been a careful observer of events and has left a detailed and clear testimony of them in his book Memorie di un novantenne, Trieste e l'Istria, where he sums up these memories; the ones of the years he has spent in Pirano before the first world war and many others, to prove his intense diplomatic activity during the second world war. And at the end he writes: "If a human being has taken part in historical events as a private citizen or a person invested with some public responsibility, he sometimes ends up by writing an almost autobiographic work, describing facts of his own life that unfortunately are not statistically casual samples of life in general … Now that I am already ninety I have learnt an Arabian proverb that compares the death of an old man to the death of a library. Thus I have realised that in a way I am too a library that is dying. If I compare my culture and the one of my old colleagues, if I compare my experience and the experience of those who lived with me in times much more difficult than nowadays, I am aware that today's young people examine single subjects more carefully than we did. And yet they have lost that vision, both scientific and practical or political more general and less deep, that was typical of our culture and of our way of thinking and acting. The story you have read, and I like to define it a story, is an attempt of not destroying completely that library that I have only recently realised I am".

His capacity of analysing contemporary society, his capacity of devising solutions and, at times, of being in advance of his time, his clearness of mind and coherence, his wide culture and his competence in all Italian economic sectors caused him to be considered one of the greatest Italian statistics. He received many official acknowledgements for his long scientific and didactic activity, as well as for the big diplomatic contribution in the years after the second world war. We mention only some: "Diploma di Medaglia d'Oro ai Benemeriti della Scuola della Cultura e dell'Arte" (1965), "San Giusto d'Oro Trieste" (1981), "San Giorgio d'Oro Comunità degli Italiani 'Giuseppe Tartini' di Pirano" (1993).
The Italian community "Giuseppe Tartini" of Pirano, the beloved town where de Castro spent his early years, in 1993 named after him their library, that consists now of 4.200 books. In future it will receive also about 10.000 books (mainly of statistics) from de Castro's personal library; it will become an important cultural reference point for the experts of this sector all over Europe.
The Institute for the History of the Italian Risorgimento has appointed de Castro honorary member of the "Comitato di Trieste e Gorizia" as a scholar and great expert in the field of the history of Trieste of Istria and Venezia Giulia.

Though far from academic life, he is still interested in it, especially in promoting culture and the scientific research. With great generosity he has constituted the foundation "Franca e Diego de Castro" that links the two universities of Turin and Trieste. Scholarships and financing of research projects are among the most important purposes of this Foundation.

Diego de Castro died on 13th June 2003 in Roletto (Pinerolo) and he was buried in Pirano cemetery.

Rosanna Panelli

	Diego de Castro, Breve storia della mia famiglia, in Marino Bonifacio, Cognomi del Comune di Pirano, "Lasa Pur Dir", n. 11, Ed. il Trillo, Pirano, 1996, pp. 3-19. Marino Bonifacio, Cognomi del Comune di Pirano, "Lasa Pur Dir", n. 11, Ed. il Trillo, Pirano, 1996, pp. 20-24, pp. 67-82.
	Diego de Castro, La statistica giudiziaria penale, in "Annali di Statistica", Istituto Centrale di Statistica del Regno d'Italia, Serie VI, Vol. XXIV, 1932, Libreria dell'Istituto Poligrafico dello Stato, Roma, 1932, pp. 288.
	Diego de Castro, Il problema di Trieste. Genesi e sviluppi della questione giuliana in relazione agli avvenimenti internazionali (1943-1952), Cappelli, Bologna, 1953, pp. 680.
	Diego de Castro, La questione di Trieste. L'azione politica e diplomatica, dal 1943 al 1954, Lint, Trieste, 1981, vol. I, pp. 956, vol. II pp. 1112.
	Diego de Castro, Memorie di un novantenne. Trieste e l'Istria, MGS Press, Trieste, 1999, pp.262.
	Flavio Forlani, Intitolata a De Castro la biblioteca piranese, in "La voce del popolo", 16 Giugno 1997.