Alexandre, Prince of Insulae Draconis ( +Jeff Berry ) put me in touch with one of his subjects (Robert de Canterbury, Visct. O.P. & Etc) who also likes playing with words and period legal documents and I've been having a fun time looking over his blog, which can be found at http://forsooth.pbworks.com/w/page/13933257/FrontPage
Among the fun things I found there was a 1460 fealty oath given by the Duke of York and the Earl of Rutland:
Item, the said Richard duke of York, shall promise and bind him by his solemn oath, in manner and form as followeth:
In the name of God, Amen. I Richard duke of York, promise and swear by the faith and truth that I owe to almighty God, that I shall never do, consent, procure or stir, directly or indirectly, privily or openly, nor as much as in me is and shall be, suffer to be done, consented, procured or stirred, anything that may be or tend to the abridgement of the natural life of king Henry the Sixth, or to the hurt or diminishing of his reign or royal dignity, by violence or any other wise, against his freedom and liberty; but that if any person or persons, would do or presume anything to the contrary, I shall with all my power and might withstand it, and make it to be withstood as far as my power will stretch thereunto; so help me God, and these holy evangelists.
Item, Edward earl of March, and Edmund earl of Rutland, the sons of the said Richard duke of York, shall make like oath.
I am completely stealing this for Saturday :-) +Brennan mac Fearghus +Meredith Bailin Hull , you've been warned. :-)