Huesca dates from pre-Roman times, and was once known as Bolskan (Iberian: ) in the ancient Iberian language. It was once the capital of the Vescetani, in the north of Hispania Tarraconensis, on the road from Tarraco (modern Tarragona) and Ilerda (modern Lleida) to Caesaraugusta (modern Zaragoza). During Roman times, the city was known as Osca, and was a Roman colony under the rule of Quintus Sertorius, who made Osca his base. The city minted its own coinage and was the site of a prestigious school founded by Sertorius to educate young Iberians in Latin and Roman customs. After Sertorius, it is thought that it was renamed Ileoscan (Ἰλεόσκαν) by Strabo. It appears to have been situated on silver mines.
Eighteenth-century Spanish historian Enrique Flórez has pointed out the impossibility of one city supplying such vast quantities of minted silver as has been recorded by ancient writers under the terms argentum Oscense, signatum Oscense; and is of the opinion that "Oscense" meant "Spanish", being a corruption of "Eus-cara". The Romanised city was made a municipium by decree of Augustus in 30 BC.