Although Katharevousa was introduced relatively recently, the concept of a conservative literary version of Greek had been present since the times of
Koine Greek. There had always existed a tendency towards a state of
diglossia between the
Attic literary language and the constantly developing spoken Koine, which eventually evolved into
Demotic Greek.
Medieval Greek texts and documents of the
Byzantine Empire were almost always written in conservative literary Greek. Examples of texts written in vernacular Greek prior to the 13th century are very rare. It can be argued that the establishment of Katharevousa was an official declaration and standardization of the conservative form of Greek, which had already existed in one way or another. The first known use of the term
Katharevousa is in a work by the Greek polymath
Nikephoros Theotokis, in 1796. Katharevousa was widely used in public documents and whatever was conceived as work of formal activity by Greek scholars. The name
Katharevousa implies a pure form of Greek as it might hypothetically have evolved from ancient Greek without external influences, while in its modern connotation the word has come to mean "formal language". In later years, Katharevousa was used for official and formal purposes (such as politics, letters, official documents, and newscasting), while Demotic Greek (, ), or popular Greek, was the daily language. This created a
diglossic situation whereby most of the Greek population was excluded from the public sphere and advancement in education unless they conformed to Katharevousa. In 1976, Demotic was made the official language, and in 1982
Andreas Papandreou abolished the polytonic system of writing; by the end of the 20th century full Katharevousa in its earlier form had become obsolete. Much of the vocabulary of Katharevousa and its grammatical and syntactical rules have influenced the Demotic language, so that the project's emphasis has made an observable contribution to the language as it is used today.
Modern Greek might be argued to be a combination of the original Demotic and the traditional Katharevousa as stressed in the 19th century, also with institutional input from Koine Greek. Among Katharevousa's later contributions are the promotion of classically based compounds to describe items and concepts that did not exist in earlier times, such as "newspaper", "police", "automobile", "aeroplane" and "television", rather than borrowing new words directly from other languages. == Etymology ==