The Roman province

Roman province

In Ancient Rome, a province was the basic, and, until the Tetrarchy , largest territorial and administrative unit of the empire's territorial possessions outside of Italy...

 of Macedonia was officially established in 146 BC, after the Roman general Quintus Caecilius Metellus

Quintus Caecilius Metellus Macedonicus

Quintus Caecilius Metellus Macedonicus was a Praetor in 148 BC, Consul in 143 BC, Proconsul of Hispania Citerior in 142 BC and Censor in 131 BC. He was the oldest son of Quintus Caecilius Metellus and grandson of Lucius Caecilius Metellus.A brilliant general, he fought in the Third Macedonian War...

 defeated Andriscus of Macedon, the last Ancient King of Macedon

Macedon

Macedonia or Macedon was an ancient kingdom, centered in the northeastern part of the Greek peninsula, bordered by Epirus to the west, Paeonia to the north, the region of Thrace to the east and Thessaly to the south....

 in 148 BC, and after the four client republics ("tetrarchy

Tetrarchy

The term Tetrarchy describes any system of government where power is divided among four individuals, but usually refers to the tetrarchy instituted by Roman Emperor Diocletian in 293, marking the end of the Crisis of the Third Century and the recovery of the Roman Empire...

") established by Rome in the region were dissolved. The province incorporated ancient Macedon, Epirus

Epirus (ancient state)

Epirus was an ancient Greek state, located in the geographical region of Epirus, in the western Balkans. The homeland of the ancient Epirotes was bordered by the Aetolian League to the south, Thessalia and Macedonia to the east and Illyrian tribes to the north...

, Thessaly

Thessaly

Thessaly is a traditional geographical region and an administrative region of Greece, comprising most of the ancient region of the same name. Before the Greek Dark Ages, Thessaly was known as Aeolia, and appears thus in Homer's Odyssey....

, and parts of Illyria

Illyria

In classical antiquity, Illyria was a region in the western part of the Balkan Peninsula inhabited by the Illyrians....

, Paeonia

Paeonia

Paeonia or Paionia may refer to:*the generic name of the peony*the ancient tribe and kingdom of Paeonia , in today's northern Greece and the Republic of Macedonia*Paionia , a municipality in northern Greece...

 and Thrace

Thrace

Thrace is a historical and geographic area in southeast Europe. As a geographical concept, Thrace designates a region bounded by the Balkan Mountains on the north, Rhodope Mountains and the Aegean Sea on the south, and by the Black Sea and the Sea of Marmara on the east...

.
After the reforms of Diocletian

Diocletian

Diocletian |latinized]] upon his accession to Diocletian . c. 22 December 244  – 3 December 311), was a Roman Emperor from 284 to 305....

 in the late 3rd century, Epirus Vetus was split off, and sometime in the 4th century, the province of Macedonia itself was divided into Macedonia Prima in the south and Macedonia Salutaris in the north.