Taksony was the son of Zoltán (the third grand prince of the Hungarians), according to the Gesta Hungarorum (written around 1200). The same source adds that Taksony's mother was an unnamed daughter of , a local ruler defeated by the conquering Hungarians shortly before 907. Its unknown author also says that Taksony was born "in the year of Our Lord's incarnation 931". The Gesta Hungarorum reports that Zoltán abdicated in favor of Taksony in 947, three years before his own death.
However, modern historians have challenged existing information on Taksony's early life. A nearly-contemporaneous source – Liudprand of Cremona's Retribution – narrates that Taksony led a plundering raid against Italy in 947, which suggests that he was born considerably earlier than 931. His father's reign was preserved only in the Gesta Hungarorum; its anonymous author lists Zoltán among the grand princes, and all later Hungarian monarchs were descended from him. The Byzantine Emperor Constantine VII Porphyrogenitus wrote around 950 that Fajsz, Taksony's cousin, was grand prince of the Hungarians at that time.
In that time Taxis, king of the Hungarians came to Italy with a large army. Berengar gave him ten measures of coins not from his own money, but from an exaction on the churches and paupers.