According to written documents, the appearance of this breed has not changed greatly from the 14th century to the present day. Probably because it possesses an excellent hereditary instinct for working sheep and cattle, selection on the basis of usability was being carried out spontaneously, which has resulted also in the balance of its look.The earliest written document about Croatian Sheepdogs, named “Canis pastoralis croaticus”, found in the archives of the diocese of Đakovo by the "father of the breed" - veterinarian Prof Dr Stjepan Romić - is from 1374. In this document, Petar, Bishop of Đakovo, says "the dog is about 18 inches high, with medium long black curly coat, the hair on the head is short, ears are pricked or semi-pricked and it is very good for keeping flocks of all farm animals."
He also mentions that the Croats brought the dog with them while migrating from their original native land to Croatia in the 7th century. Romić also found in archive of Đakovo's diocese important information from Years 1719, 1737, 1742 and 1752.
In all of these documents the description of the Croatian Sheepdog matches entirely its appearance today and in all of them the dog is named Canis pastoralis croaticus or Croatian Sheepdog.
A systematic selection breeding program was started by the same Prof Romic in 1935 with dogs in the territory of Đakovo. After 34 years of work, breed was finally recognized by FCI in 1969.