Planctus cygni

The Swan Sequence (incipit: Clangam, filii "I shall cry out, my sons") is an anonymous Carolingian–Aquitainian Latin sequence first recorded around 850. Its melody was popular for some two centuries after its composition.

In the sequence the swan has left the flowery land and is trapped on the ocean amidst terrible waves, unable to fly away. She longs for fish, but is unable to catch them; she looks up longingly at Orion. She prays for light to replace her darkness and, when the dawn finally comes, rises to the stars and flies to land. Then all the birds rejoice, praise God, and sing a doxology. In language it is neither classical Latin nor unlearned. Two neologisms (alatizo, "I flap my wings", and ovatizans, "rejoicing") appear, based on Greek. In general the poem exhibits verbal enigma and experimentation. Structurally the poem is syllabic with proparoxytone rhythm and inconsistent (half-)rhymes; it consistently ends on the sound -a. This last feature (assonance) may suggest a connexion with the liturgical Alleluia.

In the manuscripts in which it appears without text, its melody is called the Planctus cygni ("Swan's Lament") or variants thereof. It was used for Sunday church services at Limoges and Winchester during the tenth century. During the eleventh it was a common melody for liturgical texts for the feast of the Holy Innocents (28 December); during the twelfth it was a common setting for Whitsun sequences in southern France and northern Spain. Its melody differs in important ways from Gregorian chant and shares some characteristics with the lai. It is remarkably similar to another sequence, the Berta vetula of the Winchester Troper.

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