By the 3rd century BCE, Qataban, Hadramout and Ma'in became independent from Saba and established themselves in the Yemeni arena. Minaean rule stretched as far as Dedan, with their capital at Baraqish. The Sabaeans regained their control over Ma'in after the collapse of Qataban in 50 BCE. By the time of the Roman expedition to Arabia Felix in 25 BCE, the Sabaeans were once again the dominating power in Southern Arabia. Aelius Gallus was ordered to lead a military campaign to establish Roman dominance over the Sabaeans. The Romans had a vague and contradictory geographical knowledge about Arabia Felix or Yemen. The Roman army of ten thousand men reached Marib, but was not able to conquer the city, according to Cassius Dio and Pliny the Elder Strabo's close relationship with Aelius Gallus led him to attempt to justify his friend's failure in his writings. It took the Romans six months to reach Marib and sixty days to return to Egypt. The Romans blamed their Nabataean guide and executed him for treachery. No direct mention in Sabaean inscriptions of the Roman expedition has yet been found.