The city expanded and became a significant political and economical centre, more so as it became one of the first Roman cities where Christianity was recognised as an official religion (under Galerius). The Edict of Toleration by Galerius was issued in 311 in Serdica by the Roman emperor Galerius, officially ending the Diocletianic persecution of Christianity. The Edict implicitly granted Christianity the status of "religio licita", a worship recognised and accepted by the Roman Empire. It was the first edict legalising Christianity, preceding the Edict of Milan by two years.