Xenelasia

Xenelasia (Ancient Greek: ξενηλασία, Ancient Greek: [ksenɛːlasía]) was the practice in ancient Doric Crete and Lacedæmonia of expelling foreigners deemed injurious to the public welfare. The isolationist customs of Sparta (which included discouraging Spartan citizens from traveling outside the commonwealth) may also sometimes be referred to as xenelasia. The majority of ancient Greek authors attribute the codification of this practice to Lycurgus.

Xenelasia is most famously associated with Sparta. Lacedæmonian magistrates had the authorization to expel any person who posed a threat to public order and morals, for they considered their state a family writ large. While foreigners were allowed in for religious festivals and missions of state, they were generally not permitted to live in the environs, though special exceptions might be given to friends and allies, (laconophiles) like Xenophon. Conversely, the general populace was forbidden foreign travel. These laws were intended to preserve the native character of the Doric tribe from any taint of foreign influence. The greatest compliment that could be given to a Greek was that he maintained the customs of his forefathers. Prof. Karl Otfried Müller writes that the Doric ideal of a "certain loftiness and severity of character" was preserved in Sparta only because it succeeded in keeping herself in an isolated situation. Müller wrote in the context of a racial, mythographic view of history - they were the invading and occupying force in Lacedaemonia, holding down a population of servile peasants by iron military rule, and so, themselves, in the strict sense, xenoi.

Plutarch wrote:

"And this was the reason why he (Lycurgus) forbade them to travel abroad, and go about acquainting themselves with foreign rules of morality, the habits of ill-educated people, and different views of government. Withal he banished from Lacedaemon all strangers who would not give a very good reason for their coming thither; not because he was afraid lest they should inform themselves of and imitate his manner of government (as Thucydides says), or learn anything to their good; but rather lest they should introduce something contrary to good manners. With strange people, strange words must be admitted; these novelties produce novelties in thought; and on these views and feelings whose discordant character destroys the harmony of the state. He was as careful to save his city from the infection of foreign bad habits, as men usually are to prevent the introduction of a pestilence."

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Wikipedia