What is the oldest written source in this country that mentions this right?
South Africa
Freedom of expression was first protected under South Africa’s Interim Constitution of 1993. Article 15(1) specifically defines the right.
“Constitution of the Republic of South Africa Act 200 of 1993 [repealed].” Government of South Africa. Accessed July 13, 2023. https://www.gov.za/documents/constitution/constitution-republic-south-africa-act-200-1993#Fundamental%20Rights