According to his opinion, this command was initially, even before the Hungarian conquest of the Carpathian Basin around 895, bestowed upon the heir to the supreme head of the Hungarian tribal federation, in accordance with the customs of the Turkic peoples of the Eurasian steppes. Therefore, Györffy continues, the crown prince's command over these ethnic groups transformed, in the course of the 10th century, into his authority over the territories where they settled. On the other hand, Gyula Kristó, who rejected Györffy's theory, writes that the Duchy only came into being when King Andrew I granted one-third of his kingdom to his younger brother, Béla around 1048. He cites the Illuminated Chronicle which clearly states that this was the "first division of the kingdom".