Used especially as the last item in a list of people or organisations, the phrase Uncle Tom Cobley and all means everybody imaginable.

This phrase alludes to the names listed in the Devon ballad Widdecombe Fair (or Widdicombe Fair); the following version is from Songs & Ballads of the West. A Collection made from the Mouths of the People (London, 1892), by Sabine Baring-Gould (1834-1924) and Henry Fleetwood Sheppard (1824-1901):

                                                             Widdicombe Fair.
                                                                          1
“Tom Pearse, Tom Pearse, lend me your grey mare,
All along, down along, out along, lee.
For I want for to go to Widdecombe Fair,
Wi’ Bill Brewer, Jan Stewer, Peter Gurney, Peter Davy, Dan’l Whiddon, Harry Hawk, old Uncle Tom Cobleigh and all,”
Chorus. Old Uncle Tom Cobleigh and all.
                                                                         2
“And when shall I see again my grey mare?”
All along, &c.
“By Friday soon, or Saturday noon,
Wi’ Bill Brewer, Jan Stewer, &c.
                                                                         3
Then Friday came, and Saturday noon,
All along, &c.
But Tom Pearse’s old mare hath not trotted home,
Wi’ Bill Brewer, &c.
                                                                         4
So Tom Pearse he got up to the top o’ the hill
All along, &c.
And he seed his old mare down a making her will
Wi’ Bill Brewer, &c.
                                                                         5
So Tom Pearse’s old mare, her took sick and died.
All along, &c.
And Tom he sat down on a stone, and he cried
Wi’ Bill Brewer, &c.
                                                                         6
But this isn’t the end o’ this shocking affair,
All along, &c.
Nor, though they be dead, of the horrid career
Of Bill Brewer, &c.
                                                                         7
When the wind whistles cold on the moor of a night
All along, &c.
Tom Pearse’s old mare doth appear, gashly white,
Wi’ Bill Brewer, &c.
                                                                          8
And all the long night be heard skirling and groans,
All along, &c.
From Tom Pearse’s old mare in her rattling bones,
And from Bill Brewer, Jan Stewer, Peter Gurney, Peter Davy, Dan’l Whiddon, Harry Hawk, old Uncle Tom Cobleigh and all,
Chorus. Old Uncle Tom Cobleigh and all.

In the preface to the collection of songs, Sabine Baring-Gould explained the following about Widdecombe Fair:

At present the best known and most popular of Devonshire songs. The original Uncle “Tom Cobleigh” lived in a house near Yeoford Junction. The names in the chorus all belonged to Sticklepath.

An allusion to the song appeared in Trewman’s Exeter Flying Post (Exeter, Devon) of Saturday 9^th September 1893: it published an article titled A midnight row at Topsham. “Uncle Tom Cobley and all.”, about an assault that had taken place on 24^th August, during which a man named Cobley, who was “delirious from drink”, broke down the back door of the house of a certain George Denham and threatened the household.

The earliest instance of the phrase that I have found is in an extended form; it is also from Trewman’s Exeter Flying Post, which published the following on Saturday 10^th December 1898:

Quite unexpectedly and somewhat suddenly I was during the week invited to join in the hebdomadal gathering of the Oyster Club, to whose establishment reference was made in this column last Saturday. It was all O.K.—or O.C. A pleasant little party, a plenitude of oysters, and comfortable surroundings. As the song says, what could you wish for more? There was the Chairman, Bill Brewer, Peter Gurney, Dan’l Whiddon, ’Arry’ Awke, old Uncle Tom Cobley, and all.

The earliest instance of Uncle Tom Cobley and all in its current form that I have found is from the following paragraph published in The Western Times (Exeter, Devon) of Friday 13^th January 1899:

Oh! you needn’t pretend you were going to ask me what I would take. Whiskey? Certainly not after the Glasgow slump. I knew a countryman once. He lived out Twitchen way, and had a mouth like a lime kiln, and a friend asked him what he would take, and he said as he opened his mouth for a hearty guffaw, “Why just a thimbleful of port nothing else, aha! only a thimbleful of port,” and he laughed again. I always like to follow a good example, and will, to show that I’m not proud, take just a thimbleful of claret, nothing more, and here’s to your health Mr President, Mr Vice, the Secretary, and Uncle Tom Cobley and all.