Berthold IV , a member of the House of Andechs, was Margrave of Istria and Carniola .
Berthold was the son of Count Berthold III of Andechs and his wife Hedwig of Wittelsbach. His father had been a loyal liensman of Emperor Frederick Barbarossa and in turn was enfeoffed with the Istrian march upon the death of the Sponheim margrave Engelbert III. After Emperor Frederick deposed Duke Henry the Lion in 1180, his mother's relative Otto of Wittelsbach received the Duchy of Bavaria, while Berthold was appointed Duke of Merania.
About 1180/82 he already bore the title of a Duke of Merania, that is, the Adriatic seacoast of Dalmatia and Istria. Young Berthold IV first appeared in 1170 and was mentioned as Count of Andechs in a 1172 deed. In 1175 he served as co-ruler in the March of Istria.
The rule over "Merania" actually encompassed the same area as the old Istrian margraviate, but its ruler now gained much prestige from his new title and the comital House of Andechs was elevated to Princes of the Holy Roman Empire. In 1189, he led the third division of the imperial army and was its standard-bearer on the Third Crusade. In 1195, he appeared as Vogt (reeve) of Tegernsee Abbey in Bavaria.
Berthold committed himself to join the Crusade of 1197, however, he did not participate until Henry's death in the same year. At this juncture, the House of Andechs was at the height of its power and influence, with extended possessions stretching from Franconia down to the Adriatic. Berthold died in 1204 and was buried at the Andechs private monastery in Dießen, Bavaria.
About 1180, Berthold married Agnes of Rochlitz (died 25 March 1195), a daughter of Margrave Dedi III of Lusatia from the Saxon House of Wettin.