The year 1521 saw, at Câmpulung Muscel, the former Wallachian residence capital, the writing in Romanian of the first compact and unitary document of all that are known to us up to the present day. It is the letter of Neacşu ot Dlăgopole (present Câmpulung Muscel city, Argeş county, Romania), dated on the 29th or the 30th of June 1521. The letter contained a secret of great importance, warning the mayor of Braşov city, Johannes Benkner, about a Turkish invasion, prepared in the south of the Danube, to be directed against Transylvania and Wallachia.