After Maxentius’ defeat, Constantine gradually consolidated his military superiority over his rivals in the crumbling Tetrarchy. In 313, he met Licinius in Milan to secure their alliance by the marriage of Licinius and Constantine's half-sister Constantia. During this meeting, the emperors agreed on the so-called Edict of Milan, officially granting full tolerance to "Christianity and all" religions in the Empire. The document had special benefits for Christians, legalizing their religion and granting them restoration for all property seized during Diocletian's persecution. It repudiates past methods of religious coercion and used only general terms to refer to the divine sphere — "Divinity" and "Supreme Divinity", "summa divinitas". The conference was cut short, however, when news reached Licinius that his rival Maximinus had crossed the Bosporus and invaded European territory. Licinius departed and eventually defeated Maximinus, gaining control over the entire eastern half of the Roman Empire. Relations between the two remaining emperors deteriorated, though, and either in 314 or 316, Constantine and Licinius fought against one another in the war of Cibalae, with Constantine being victorious. They clashed again in the Battle of Campus Ardiensis in 317, and agreed to a settlement in which Constantine's sons Crispus and Constantine II, and Licinius' son Licinianus were made "caesars".