Archbishop Petar Bogdan is an indisputable phenomenon of his time, President Rumen Radev said at the presentation of the reproduction of the manuscript "On the Antiquity of the Fatherland and the Bulgarian Affairs" in the Coat of Arms Hall of the Presidency building. "Today, we are particularly excited to come into contact with his work", Rumen Radev pointed out. 

The manuscript is the first historical treatise dedicated to Bulgaria, written in Latin and completed around 1667. The 200 page manuscript examines the Christian past and present of the Bulgarian lands. It aims to mobilize support in the then Catholic Europe for the liberation of Bulgaria from Ottoman rule. The manuscript was long thought to be lost. In 2017, Professor Lilia Ilieva discovered the manuscript of the oldest history of Bulgaria. It is part of the collection of Marquis Campori in the Estense University Library in Modena.