toured the area in 1166, recorded that the town of Zetouni (Lamia) was "situated at the foots of the hills of Vlachia". The term was evidently not simply a geographic or ethnic designation, for a chrysobull of Emperor Alexios III Angelos (r. 1195–1203) in 1198 includes the Provincia Valachie among the districts of Thessaly where Venetian merchants were granted exemptions, and the same information is repeated in the list of provinces granted to Boniface of Montferrat in the Partitio Romaniae of 1204. According to the Byzantinist George C. Soulis, from this information it appears that this late 12th-century Byzantine province of Vlachia "was situated in the Mount Othrys region, occupying the area lying between the towns of Lamia, Domokos and Halmyros". Despite their prominence in Thessaly, however, the Vlachs never came to rule over the region, submitting instead to the various Greek, Latin, and later Serb rulers. Following the Fourth Crusade and the capture of Thessaly by the Despotate of Epirus, the Vlachs were used by the Epirotes as elite troops against their rivals; the 13th-century scholar George Pachymeres comments on the bravery of the Megalovlachitai in the army of the ruler of Epirus, Michael II Komnenos Doukas (r. ca. 1230–1268). Michael's bastard son, John, was married to a Vlach, the daughter of the chieftain Taron, and his Vlach troops—it is unclear whether they were regular forces or perhaps a private army raised from his estates—played a prominent role in the Battle of Pelagonia in 1259. When Michael II died in ca. 1268, his realm was divided, and John became ruler of Thessaly, with his capital at Neopatras. Western authors often used the term "Vlachia" to refer to the autonomous Thessalian realm of John Doukas and his heirs. Part of Thessaly, however, around Demetrias, Velestino, Halmyros, and Pharsalos, had remained in the hands of the Nicaean Empire, and after 1261 the restored Byzantine Empire, for several years after Pelagonia. This district was governed by a "kephale of Great Vlachia", a post held in 1276 by the pinkernes Raoul Komnenos. After the conquest of large parts of the Byzantine Empire in the mid-1340s, the Serbian ruler Stefan Dushan was crowned emperor in 1346, founding the Serbian Empire. In 1347–1348 he and his general Preljub extended Serbian control over Epirus and Thessaly. Afterwards, Stefan Dushan claimed the titles, in Latin, of imperator Raxie et Romanie, dispotus Lartae et Blachie comes ("Emperor of