Great late medieval Spanish chant by Chanticleer of San Francisco- Picture from their "Portrait" Album, and they own the copyrights to all of this, I am merely posting so that we may all enjoy their amazing music.
If you played Europa Universalis 2, you'll recognize this song from the 15th century period, this was played a lot.
Lyrics from http://okay.com/renaissance/riuchiulyrics.htm:
Riu, riu, chiu (nightingale's sounds)
The river bank protects it,
As God kept the wolf
from our lamb.
The rabid wolf tried to bite her,
But God Almighty knew how to defend her,
He wished to create her impervious to sin,
Nor was this maid to embody original sin.
Riu, riu, chiu, etc.
The newborn child is the mightiest monarch,
Christ patriarchal invested with flesh.
He made himself small and so redeemed us:
He who was infinite became finite.
Riu, riu, chiu, etc.
Many prophecies told of his coming,
And now in our days have we seen them fulfilled.
God became man, on earth we behold him,
And see man in heaven because he so willed.
Riu, riu, chiu, etc.
A thousand singing herons I saw passing,
Flying overhead, sounding a thousand voices,
Exhulting, "Glory be in the heavens, and peace on Earth, for Jesus has been born."
Riu, riu, chiu, etc.
He comes to give life to the dead,
He comes to redeem the fall of man;
This child is the light of day,
He is the very lamb Saint John prophecied.
Riu, riu, chiu, etc.
Now we have gotten what we were all desiring,
Go we together to bear him gifts:
Let each give his will to the God who was willing
To come down to Earth mans equal to be.
Riu, riu, chiu, etc.