He was born in
Heraklion, Crete. He was the son of Gerasimos Hatzidakis. Manolis showed an interest in art from a young age. During his early life, post-Byzantine art was relatively unknown. Greek diplomat and historian Dimitrios Sicilianos was one of the early proponents of the field. He published a book in 1935, called
Greek Hagiography after the Fall (1450 - 1800). Hatzidakis decided to study and contribute to Greek art. He studied at the
University of Athens. He attended the School of Philosophy. He graduated in 1933, but did not receive a doctorate until 1942. In 1941, he became the director of the
Benaki Museum. He remained at this position until 1973. He was also affiliated with the Archaeological Institute of Greece in 1943. He was director of Byzantine research. By 1961, he was special evaluator of Byzantine and Post Byzantine art. Six years later he was the head of research. By the 1950s, the Greek government was in possession of
San Giorgio dei Greci and
Santi Pietro e Paolo dei Greci, two historic Greek churches in Italy. The
Hellenic Institute of Venice was founded to help research post-Byzantine art affiliated with the institution by the Ministries of Education and Foreign Affairs. The collection of the two churches houses over 400 artifacts. Hatzidakis was crucial in contributing to the vast research. In 1953, Hatzidakis was sent to
Zakinthos immediately after the earthquake, countless Greek artifacts were lost and destroyed from the fires. Hatzidakis helped save 900 undamaged works of art. He was also part of countless archeological expeditions all over the world. In 1962, there was a grand exhibition of art organized by the European council. He was appointed secretary-general. The massive exhibition was held in Athens, Greece at the
Zappeion, in September 1964. It was titled
Byzantine and European Art. Around the same period, he carried out research on
Mount Athos,
Church of the Holy Sepulchre,
Saint Catherine's Monastery,
Ionian Islands,
Crete and
Venice. He was also special representative of the
Patriarchate of Jerusalem in the three-member committee for the restoration of the
Church of the Holy Sepulchre during the mid-sixties and seventies. In 1960, he was also the director of the
Byzantine and Christian Museum. He was disrupted under the
Greek junta they confiscated his passports and removed him from the position. He continued minor duties under the military dictatorship. In 1973, he took over the direction of the Byzantine Antiquities of Athens. When the
Greek junta was overthrown, he returned as director of the
Byzantine and Christian Museum. He retired one year later. He was a prominent member of the Greek Archaeological Council. He resigned in protest in 1977, he was 68 years old. The Greek government passed legislation that changed the composition of the council and transferred its responsibilities to the Ministries of Finance and Coordination. In 1987, he published
Greek painters after the Fall of Constantinople (1450 - 1830) Volume A, the second version was published in 1997,
Greek painters after the Fall of Constantinople (1450 - 1830) Volume B. The books featured hundreds of biographies about Greek painters including
Georgios Klontzas,
Emmanuel Tzanes, and
Michael Damaskinos. He died in 1998. He was buried at the
First Cemetery of Athens. He was a member of countless organizations and institutions. Hatzidakis was secretary of the Society of Byzantine Studies. He also served as secretary and president of the Christian Archeological Society. He was vice president of the board for the Educational Institute of the National Bank of Greece. He was a member of the German Archeological Institute. He received two honorary doctorates from the University of Brussels and Athens. He was an associate member of the Academy of Sciences of Vienna and Belgrade. He was a member of the Academy of Athens in 1980. He was the secretary of the organization from 1981-1990. In 1985, he was appointed chairman of the Organizing Committee of the Byzantine Art Exhibition, he was 76 years old. He taught courses at various educational institutions. He was the principal advisor for the restoration of countless works of art at their laboratories. He was also an advisor at the Byzantine and Post-Byzantine Art Research Center of the Academy of Athens. Throughout his lifetime he was awarded the
Order of the Phoenix,
Herder Prize (1965), and the
Order of George I.{{cite web ==Literary works==