[citation needed] The Slavs organized themselves into "Sklaviniai", that continued to assault the Byzantine Empire, either independently, or aided by Bulgars or Avars during the 7th century.

[2][4] Its creation came in the aftermath of a series of military successes that had extended Byzantine reach over most of the wider region of Thrace, and was probably intended to make imperial control more efficient by entrusting the greatly expanded territory to two strategoi.

[citation needed] The core area of the old theme of Macedonia was recorded as the "province of Adrianople and Didymoteichon" (provincia Adrianupoleos et Didimotichi).

The Arab geographers Ibn Khordadbeh (wrote c. 847) and Ibn al-Faqih (wrote c. 903), whose accounts are a major source on the Byzantine themes, mentioned that the theme of Macedonia (Maqaduniya) extended from the "Long Wall" (the Anastasian Wall) to the "lands of the Slavs" in the west, and from the Aegean and Marmara Seas to the borders of Bulgaria to the north.

He received an annual salary of 36 pounds of gold (2,592 nomismata), and, according to the account of Ibn al-Faqih, in the late 9th century controlled 5,000 troops.

[10][11] Strymon, which was originally a kleisoura of Macedonia, was split off sometime in the early 9th century, taking some 2,000 men (according to the estimate of historian Warren Treadgold) along with it.