While the banshee - by name at least, is confined to Irish folklore, being derived from 'bean sidhe', the 'woman of the fairies' (or ‘woman of the hill’), she - ghost or archetype, depending on your point of view - is reflected in recognisably similar characters found in Celtic, European, and other traditions. Similar stories abound of the beautiful maiden/hag character - the classic femme fatale - who beguiles men, leading them toward or foretelling impending death.
In the Celtic stream, for instance, there is the bean nighe, of Ireland and Scotland - the Washer of the Ford, an ugly hag that sometimes appeared in the guise of a beautiful young woman, and who, akin to the banshee, portended death by her appearance.
In European lore, there is the Rusalka, water spirit of Slavic lore said to be the spirit of a dead female (in some parts, a bride who died on her wedding night) who, like the Sirens of Greek mythology, lure men their drowning by sweet song; the Vila, another hostile spirit of Slavic lore, the spirit of an unbaptized child or an earthbound virgin. The vila dances in circles, condemning any who disturb them to join them unto death; the Nocnitsa, a hag of Eastern European lore; the Berchta, an ugly old woman of German folklore, thought to have orginally been a goddess (the German equivalent of the Cailleach); the nix, a German equivalent of the Rusalka; the acheri of Native American lore; the anhanga of the Brazilian Amazon.
It is interesting to note that powers of prophecy (even to the foretelling of death) most commonly attributed to the darker (and by time-honoured interpretation, evil) characters of this lore, were frequently old crones wizened by age.
Sometimes, though, as mentioned, the banshee could take the guise of a young female...
and, in real-life reports, the banshee-like cry is heard within the context of another unlikely-sounding but verified scenario - such as the intriguing encounter in May 1976 when Anton Le Grange from Oudtshoorn, South Africa, met a female hitch-hiker some 13 kilometres from Uniondale:
It was dark; the time was 7.15 p.m. The rain and coldness prompted him to offer a lift to the woman although she did not appear to be actually seeking a lift. She was dressed in dark trousers and jacket. Her hair, contrary to that depicted in rumour, was dark, and her face pale.
The girl accepted the offer of a lift, giving the address to which she wished to be taken. It was shortly after pulling away that Le Grange thought to question the girl about the destination address, recalling that there was no such street in Oudtshoorn, his own destination. On looking over his shoulder, he found she had disappeared.
The incident was duly reported to Uniondale police. The duty officer at the time, PC Snowy Potgieter, recalled that Le Grange had been upset but sober, and agreed to drive out to the scene of the incident. On the way out there, the police officer (following in his own vehicle) witnessed the right rear door of Le Grange's car open and close by itself. Le Grange reported that he heard a 'spine-chilling' laugh inside his car. (A slightly different version states that Le Grange was driving away from the police station when he heard a horrible scream inside his vehicle, in response to which he immediately turned back. Officer Potgieter then accompanied the witness on the way back to the scene of the incident, during which the door-opening event occurred.
read more here
http://www.tudor34.freeserve.co.uk/Cases-World.htm#Union
And we can return to the same pool of lore, and recognise similar traits with the more recognisably elemental forms of these creatures - boggarts, for instance, that fly shrieking into the night after surprising and terrifying unwary travellers by night...
