Crestonia was an ancient region immediately north of Mygdonia

Mygdonia (Europe)

Mygdonia was an ancient territory, part of Ancient Thrace, later conquered by Macedon, which comprised the plains around Therma together with the valleys of Klisali and Besikia, including the area of the Axios river mouth and extending as far east as Lake Bolbe. To the north it was joined by...

. The Echeidorus river, which flowed through Mygdonia into the Thermaic Gulf

Thermaic Gulf

The Thermaic Gulf is a gulf of the Aegean Sea located immediately south of Thessaloniki, east of Pieria and Imathia, and west of Chalkidiki . It was named after the ancient town of Therma, which was situated on the northeast coast of the gulf...

, had its source in Crestonia. It was partly occupied by a remnant of the Pelasgi

Pelasgians

The name Pelasgians was used by some ancient Greek writers to refer to populations that were either the ancestors of the Greeks or who preceded the Greeks in Greece, "a hold-all term for any ancient, primitive and presumably indigenous people in the Greek world." In general, "Pelasgian" has come...

, who spoke a different language from their neighbors (Thracians

Thracians

The ancient Thracians were a group of Indo-European tribes inhabiting areas including Thrace in Southeastern Europe. They spoke the Thracian language – a scarcely attested branch of the Indo-European language family...

 and Paeonians); later the Greeks

Greeks

The Greeks, also known as the Hellenes , are a nation and ethnic group native to Greece, Cyprus and neighboring regions. They also form a significant diaspora, with Greek communities established around the world....

.

The main towns of Crestonia were Creston

Creston

-Places:Canada* Creston, British Columbia a town in the Regional District of Central Kootenay* Creston, Newfoundland and Labrador a town in Burin peninsulaUnited States* Creston, California, an unincorporated place in San Luis Obispo County...

 (Crestone) and "Gallicum" (Romanized name). The region, along with Mygdonia, was held by Paeonians for a time, later by Thracians. At the time of the invasion of Xerxes I of Persia

Xerxes I of Persia

Xerxes I of Persia , Ḫšayāršā, ), also known as Xerxes the Great, was the fifth king of kings of the Achaemenid Empire.-Youth and rise to power:...

, Crestonia was ruled by an independent Thracian prince (Herodotus

Herodotus

Herodotus was an ancient Greek historian who was born in Halicarnassus, Caria and lived in the 5th century BC . He has been called the "Father of History", and was the first historian known to collect his materials systematically, test their accuracy to a certain extent and arrange them in a...

, 8. 116). By the time of the commencement of the Peloponnesian war

Peloponnesian War

The Peloponnesian War, 431 to 404 BC, was an ancient Greek war fought by Athens and its empire against the Peloponnesian League led by Sparta. Historians have traditionally divided the war into three phases...

, Crestonia had been annexed to the kingdom 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....

.

Today, ancient Crestonia is comprehended within the prefectures of Kilkis

Kilkis Prefecture

Kilkis is one of the regional units of Greece. It is part of the region of Central Macedonia. Its capital is the city of Kilkis.-Geography:The mountains near Kilkis are Paiko to the west, parts of the western part of Kerkini to the northeast and Krousia to the east...

 and part of north Thessaloniki

Thessaloniki Prefecture

Thessaloniki is one of the regional units of Greece. It is part of the Region of Central Macedonia. Its capital is the city of Thessaloniki. It is the second most populous regional unit in Greece, behind Central Athens.-Geography:...

 in Greece

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

.