Anson argues that some Hellenic authors expressed complex or even ever-changing and ambiguous ideas about the exact ethnic identity of the Macedonians, who were considered by some such as Aristotle in his "Politics" as barbarians and others as semi-Greek or fully Greek. Roger D. Woodard asserts that in addition to persisting uncertainty in modern times about the proper classification of the Macedonian language and its relation to Greek, ancient authors also presented conflicting ideas about the Macedonians. Simon Hornblower argues on the Greek identity of the Macedonians, taking into consideration their origin, language, cults and customs. Any preconceived ethnic differences between Greeks and Macedonians faded by 148BC soon after the Roman conquest of Macedonia and then the rest of Greece with the defeat of the Achaean League by the Roman Republic at the Battle of Corinth (146 BC).