What is the oldest written source in this country that mentions this right?
Greece
Article 9 of the 1975 Constitution establishes the right to privacy in people’s homes: “Every person's home is a sanctuary. The private and family life of the individual is inviolable.” Article 9A provides constitutional data privacy protections In Article 19 of the 1975 Constitution, the right to privacy in any form of communication is established: “Secrecy of letters and all other forms of free correspondence or communication shall be absolutely inviolable.”