Crown Prince of Greece

The Crown Prince of Greece (Greek: Διάδοχος, Diadochos) is the heir to the throne of modern Greece. Since the abolition of the Greek monarchy by the then-ruling military regime on 1 June 1973, it is merely considered a courtesy title.

Neither the constitution of 1844 or 1864, which served as the basis for other fundamental laws of the Kingdom of Greece, recognised titles of nobility. On the contrary, they prohibited even the sovereign from conferring such titles.

As a result, the heir apparent was usually referred to simply as "the diadochos" by virtue of his function, rather than as a title. The word diadochos (διάδοχος) simply means "successor, he who collects the estate". This is a deverbal of διαδέχομαι (diadéchomai), "receive by succession", and has been used since the Archaic period for heirs-apparent. The most famous bearers of the title were the Diadochi, the "Successors" of Alexander the Great, who contended with each other for the spoils of his empire.

Only one crown prince, the future Constantine I, bore a separate title of nobility, that of "Duke of Sparta".

The London Conference of 1832, established a semi-salic line of succession which would pass the crown to Otto I's descendants, or his younger brothers (Luitpold Karl and Adalbert Wilhelm), should he have no issue. It was also decided that in no case would the crowns of Greece and Bavaria be joined in a personal union.

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Wikipedia