The Oldest Christmas Carol?

Allegedly the earliest Christmas carol, usually dated to the thirteenth century:

Lordings, listen to our lay —
We have come from far away
    To seek Christmas;
In this mansion we are told
He his yearly feast doth hold;
    'Tis t-day!
May joy come from God above,
To all those who Christmas love.

Lordings, I now tell you true,
Christmas bringeth unto you
    Only mirth;
His house he fills with many a dish
Of bread and meat and also fish,
    To grace the day.
May joy come from God above,
To all those who Christmas love.

Lordings, through our army's band
They say — who spends with open hand
    Free and fast,
And oft regals his many friends —
God gives him double what he spends
    To grace the day.
May joy come from God above,
To all those who Christmas love.

Lordings, wicked men eschew,
In them never shall you view
    Aught that's good;
Cowards are the rable rout,
Kick and beat the grumblers out,
    To grace the day.
May joy come from God above,
To all those who Christmas love.

To English ale and Gascon wine,
And French, doth Christmas much incline —
    And Anjou's, too;
He makes his neighbour freely drink
So that in sleep his head doth sink
    Often by day.
May joy come from God above,
To all those who Christmas love.

Lords, by Christmas and the host
Of this mansion hear my toast —
    Drink it well —
Each must drain his cup of wine,
And I the first will toss off mine:
    Thus I advise.
Here then I bid you all Wassail,
Cursed be he who will not say, Drinkhail.
May joy come from God above,
To all those who Christmas love.

Wassail translates as "your health", and drinkhail as "drink health". Both terms are Anglo-Saxon in origin and really deserve to make their way back into common usuage.

The original manuscript that contained this carol has been missing since 7th June 1879, but remains listed in the British Library's catalogue as Royal MS 16 E VIII. It was found in the midst of a miscellany alongside other documents such as a "short description of England" and "phases of the moon proper for any business". 

EDIT:
This video worked up until this blog post went live which is rather typical. You can find a performed version of this song however if you search for the group "Joglaresa".

Notes 

Transcription (in Anglo-Norman) can be found in Douce, F. Illustrations of Shakespeare, and of Ancient Manners: With Dissertations on the Clowns and Fools of Shakespeare; on the Collection of Popular Tales Entitled Gesta Romanorum; and on the English Morris Dance, Volume 2 (London: Longman, Hurst, Rees, and Orme, 1807) p. 215

Rickert, E. Ancient English Chirstmas Carols: 1400-1700 (London: Chatto & Windus, 1914) pp. 134-5