Ardiaei or Ouardiaei (Ancient Greek: Ἀρδιαῖοι or Οὐαρδαῖοι; Latin: Vardiaei), was an Illyrian tribe, residing inland, that eventually settled on the Adriatic coast. Polybius (203 BC–120 BC) writes that they were subdued by the Romans at events that occurred at 229 BC. Appian (95–165) writes that they were destroyed by the Autariatae and that in contrast to the Autariatae had maritime power. In the Epitome of Livy they are said to have been subdued by the consul Fulvius Flaccus.
They were located in present day Montenegro, most likely around the gulf of Rhizon, although Strabo places them in the right bank of the Neretva. Their initial inland residence was located along the Naro River up to the Konjic region, in present-day Bosnia and Herzegovina.
There is also one other interesting feature indicating that the original homeland of Ardiaei might indeed have been the Neretva valley region. Specifically, there is a town in Bosnia and Herzegovina situated in the wider Neretva valley region (the original homeland of ancient Illyrian people of Ardiaei),called Čapljina, and its name derives from čaplja, which in former Serbo-Croatian language means 'heron'. The Latin word for heron is ardea, a word that bears striking similarity with the name of Ardiaei, and should not be excluded altogether as its potential cognate. This theory opens up many possibilities for the interpretation of the original homeland of the Ardiaei and the etymology of their name. For example, heron might have had totemic pagan value among the Illyrians inhabiting that region, due to its presence in this area, and it is not implausible to conclude that one of those Illyrian peoples named itself after a heron, the Ardiaei. The Latin word ardea might be a Latin translation of some original Illyrian word for 'heron' that Romans found when they settled in this area, or the 'ardea' itself could have been an Illyrian word taken by Romans, who might have slightly altered it and integrated it into their language, the Latin. Indeed the word Ardiaei is found in ancient Greek sources predating the arrival of Romans and their language to the Illyrian lands. It is also possible that ancient Illyrians or Romans named this place 'the place of heron(s), and the Slavic settlers, who settled in the former Illyrian lands around 6th century A.D. translated the name of this place into their language(s), which in turn gave 'Čapljina', "tha place of heron(s)".
The Ardiaei had briefly attained military might, during 230 BC under the reign of king Agron, (an Ardiaean by tribal origin). His widow, Queen Teuta attempted to gain a foothold in the Adriatic but failed due to Roman intervention. Historic accounts hold that King Agron was hired by king Demetrius of Macedonia repel the invasion of Macedonia by the invading Aetolians. The Ardiaei had 20 decuriae.
"Because they pestered the sea through their piratical bands, the Romans pushed them back from it into the interior and forced them to till the soil. But the country is rough and poor and not suited to a farming population, and therefore the tribe has been utterly ruined and in fact has almost been obliterated. And this is what befell the rest of the peoples in that part of the world; for those who were most powerful in earlier times were utterly humbled or were obliterated, as, for example, among the Galatae the Boii and the Scordistae, and among the Illyrians the Autariatae, Ardiaei, and Dardanii, and among the Thracians the Triballi; that is, they were reduced in warfare by one another at first and then later by the Macedonians and the Romans"
King Agron, son of Pleuratus who belonged to the ruling house of the Ardiaei, disposed of the most powerful force, both by land and sea, of any of the kings which had reigned in Illyria before him.
See also 
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 216, "The Ardiaei, or Vardaei as they were known to the Romans, `once the ravagers of Italy' and now reduced to a mere"
- Appian and Illyricum by Marjeta Šašel Kos, " The Ardiaei were certainly also settled in the hinterland, along the Naro River at least as far as the Konjic region..."
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 188, "probably the result of pressure from new Illyrian groups, including the Ardiaei and Delmatae, moving towards the Adriatic..."
- Plb. 2.11, "The Romans, taking the Epidamnians under their protection, advanced into the interior of Illyricum, subduing the Ardiaei as they went."
- App. Ill. 1, "In like manner the Ardiæi, who were distinguished for their maritime power, were finally destroyed by the Autarienses, whose land forces were stronger, but whom they had often defeated."
- Appian and Illyricum by Marjeta Šašel Kos, "...who located the Ardiaei in the southern Illyrian area in present-day Montenegro..."
- D. Dzino, 'Late Republican Illyrian Policy of Rome 167-60 BC: the Bifocal Approach’, in C. Deroux (ed.), Studies in Latin Literature and Roman History 12. Collection Latomus 287 [Latomus: Bruxelles 2005] pp. 48-73., "...in the vicinity of the Rhizonic gulf..."
- D. Dzino, 'Late Republican Illyrian Policy of Rome 167-60 BC: the Bifocal Approach’, in C. Deroux (ed.), Studies in Latin Literature and Roman History 12. Collection Latomus 287 [Latomus: Bruxelles 2005] pp. 48-73., "Strabo locates them on the right bank of Neretva."
- Adzanela (Axhanela) Ardian, Illyrian Bosnia and Herzegovina-an overview of a cultural legacy, 2004, Centre for Balkan Studies, Online Balkan Centre : http://www.academia.edu/2490281/Illyrian_Bosnia_and_Herzegovina-an_Overview_of_a_Cultural_Legacy_Ancient_Illyrians_of_Bosnia_and_Herzegovina
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 221, "To the Greek world the Illyrians appeared heavy drinkers, from the drinking bouts of the Ardiaei from which intoxicated men were conveyed home by their women, who had also participated, to the overindulgence of their kings..."
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 139, "...describes a long-running feud between the Autariatae and the Ardiaei over the possession of a salt-source near their common border..."
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 223, "The salt source that was a cause of conflict between the Illyrian Ardiaei and Autariatae may be that at Orahovica in the upper Neretva valley near Konjic."
- The Cambridge ancient history, Tome 7, Part 1, by Frank William Walbank, 1984, ISBN 0-521-23445-X, page 452
- Strab. 7.5
- Wilkes, J. J. The Illyrians, 1992, ISBN 0-631-19807-5, page 156-157: "Agron, son of Pleuratus belonged to the ruling house of the Ardiaei. 'Agron was king of that part of Illyrian which borders Adriatic sea, over which Pyrrhus and his successors had held sway. In turn he captured part of Epirus and also Corcyra, Epidamnus and Pharos in succession, and established garrisons in them'(Appian Illyrike 7). The new power disposed of the most powerful force, both by land and sea, of any of the kings who had reigned in Illyria before him', we are informed by Polybius (2.2)"