Its center was located in the Orăştie Mountains where Burebista had a number of fortifications erected. This forts were built by Greek craftsmen who introduced the use of chiseled stone. Strabo writes that Burebista "had as his coadjutor Deceneus, a wizard", who assisted him to stabilize his rule among the Dacians. Deceneus reformed the cult of Zalmoxis. He persuaded the Dacians "to cut down their vines and to live without wine", according to Strabo. The 6th-century historian, Jordanes, who preserved information originally recorded by Dio Chrysostom, writes that Deceneus "chose from among" the Dacians "those that were at that time of noblest birth and superior wisdom and taught them theology, bidding them worship certain divinities and holy places". These "pilleates" or "tarabostes" formed the ruling stratum of the Dacian society; the commoners were called "capillati" or "comati". Strabo writes that Burebista "was deposed" during an uprising. The year of Burebista's fall cannot exactly be determined, but most historians write that he was assassinated in 44 BC. Strabo narrates that after Burebista's death his empire fall apart and four (later five) smaller polities developed in its ruins. The names of some of their kings were recorded by Roman writers. For instance, Dicomes, "the king of the Getae, promised to come and join" Mark Antony "with a great army", according to Plutarch. A new empire dominated by the Dacians emerged in the reign of Decebalus who ruled from 87 AD. In the first year of his reign, he defeated a Roman army sent against Dacia in retaliation of a plundering raid in the Roman province of Moesia. Although the Romans defeated Decebalus in the Battle of Tapae in 88, he concluded a favorable peace treaty with the Roman Empire. It not only acknowledged Decebalus's status as "rex amicus" or client king, but the Romans also gave "large sums of money" to him "as well as artisans of every trade pertaining to both peace and war", according to Cassius Dio. Taking advantage of his treaty with the Romans, Decebalus improved the defenses of his kingdom. He also expanded his rule over the neighboring territories in the next decade.