Alania was a medieval kingdom of the Iranian Alans (proto-Ossetians) that flourished in the Northern Caucasus, roughly in the location of latter-day Circassia and modern North Ossetia–Alania, from the 8th or 9th century until its destruction by the Mongol invasion in 1238-39. Its capital was Maghas, and it controlled a vital trade route through the Darial Pass.

The Alans (Alani) originated as an Iranian-speaking subdivision of the Sarmatians. They were split by the invasion of the Huns into two parts, the European and the Caucasian. The Caucasian Alans occupied part of the North Caucasian plain and the foothills of the main mountain chain from the headwaters of the Kuban River in the west to the Darial Gorge in the east.

Alania was an important buffer state during the Byzantine-Arab Wars and Khazar-Arab Wars of the 8th century. Theophanes the Confessor left a detailed account of Leo the Isaurian's mission to Alania in the early 8th century. Leo was instructed by Emperor Justinian II to bribe the Alan leader Itaxes into severing his "ancient friendship" with the Kingdom of Abkhazia which had allied itself with Caliph Al-Walid I. He crossed the mountain passes and concluded an alliance with the Alans, but was prevented from returning to Byzantium through Abasgia. Although the Abkhazians spared no expense to have him imprisoned, the Alans refused to convey the Byzantine envoy to his enemies. After several months of adventures in the Northern Caucasus, Leo extricated himself from the precarious situation and returned to Constantinople.

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