In 977 Byzantine Thessaly was raided by the Bulgarian Empire. In 1066 dissatisfaction with the taxation policy led the Aromanian and Bulgarian population of Thessaly to revolt against the Byzantine Empire under the leadership of a local lord, Nikoulitzas Delphinas. The revolt, which began in Larissa, soon expanded to Trikala and later northwards to the Byzantine-Bulgarian border. In 1199–1201 another unsuccessful revolt was led by Manuel Kamytzes, son-in-law of Byzantine emperor Alexios III Angelos, with the support of Dobromir Chrysos, the autonomous ruler of Prosek. Kamytzes managed to establish a short-lived principality in northern Thessaly, before he was overcome by an imperial expedition.