At Muncaster Castle hangs a full-length portrait of Tom Skelton, dressed in fool's motley and holding a staff, with a document, in the form of a will, hanging beside him. Another, cruder version of the portrait used to hang at Haigh Hall near Wigan, but was sold to the Shakespeare Institute in 1957. The text of the document, as reproduced below, casts an interesting light on the whole "Tom Fool of Muncaster" legend. Only the title (omitted in the cruder version) indicates that Thomas Skelton was ever a resident at Muncaster, the poem itself specifies that when the "will" was written he lived at Haigh (shown below in an engraving from about 1700). The borough of Egremont is mentioned, as is a member of the Pennington family, but the name Nicholas Pennington is not associated with Muncaster either- it was used for several generations (particularly in the 17th century) of the branch of the family which lived in the Wigan area (see the genealogical work "Penningtoniana" by Joseph Foster, 1878).
Thanks to the wonders of online publication, subscribers to major journal back-number services can now see two articles from 1960 by E.W. Ives:
"Tom Skelton- A Seventeenth-Century Jester" in Shakespeare Survey no. 13, and
"Tom Skelton and Motley" in Notes and Queries December 1960 (New Series vol 7, no. 12)
It turns out that Ives had, all those years ago, conducted the sort of dogged research I had hoped to do some day in Lancashire, and found just enough to make a coherent story. Ralph Wayte, Nicholas Pennington and Tom Turner were all important figures around Haigh in the mid-17th century, and it seems that Skelton moved there from Muncaster in 1659, following the death of Joseph Pennington of Muncaster, whose young heir William became a ward of Sir Roger Bradshaigh of Haigh, who had married Joseph's sister Elizabeth in 1647. Ives also found that Ralph Waite was buried in January 1666 (1665 Old Style dating), thus establishing a very limited time-span during which the portrait could have been painted. Most importantly, it's a very long time after William Shakespeare created a character "Tom Fool" in the play "King Lear"- so this Tom was not the Bard's inspiration. The burial of a Thomas Scelton of Haigh is recorded in the Wigan parish register on 13 January 1668 (1667 Old Style), which fits with the late-middle-aged look of the portrait. Ives also analyses the comic/satiric aspects of the "will", looks briefly at some of the Skelton legends circulating in Cumbria (but not, it seems, around Haigh) and offers an explanation for the existence of the crude copy version of the picture- once young William Pennington came of age, and returned to Muncaster, about 1676, he was offered the original, and the Bradshaighs had the copy made for their own collection.

Thoms. Skelton late fool of Muncaster last will and Testament

Be it known to ye, oh grave and wise men all,
That I Thom Fool am Sheriff of ye Hall,
I mean the Hall of Haigh, where I command
What neither I nor you do understand.
My Under Sheriff is Ralph Wayte you know,
As wise as I am and as witty too.
Of Egremond I have Burrow Serjeant beene,
Of Wiggan Bailiff too, as may be seen
By my white staff of office in my hand,
being carried straight as the badge of my command:
A low high constable too was once my calling,
Which I enjoyed under kind Henry Rawling;
And when the Fates a new Sheriff send,
I'm Under Sheriff prick'd World without end.
He who doth question my authority
May see the seal and patten here ly by.
The dish with luggs which I do carry here
Shews all my living is in good strong beer.
If scurvy lads to me abuses do,
I'll call 'em scurvy rogues and rascals too.
Fair Dolly Copeland in my cap is placed;
Monstrous fair is she, and as good as all the rest.
Honest Nich. Pennington, honest Ths. Turner, both
Will bury me when I this world go forth.
But let me not be carry'd o'er the brigg,
Lest falling I in Duggas River ligg;
Nor let my body by old Charnock lye,
But by Will. Caddy, for he'll lye quietly
And when I'm bury'd then my friends may drink,
But each man pay for himself, that's best I think.
This is my Will, and this I know will be
Perform'd by them as they have promised me.

Sign'd, Seal'd, Publish'd, and Declared in the presence of
HENRY RAWLING
HENRY TROUGHTON
THS. TURNER

THS. SKELTON, X his Mark