Where does "dead man walking" come from?

The recent epithet used by George Osborne "dead woman walking" is a clear reference to the more common expression:

Dead man walking whose original meaning is:

• (US) a condemned man walking from his prison cell to a place of execution.

but is more commonly and informally used to refer to:

• any person in a doomed or untenable situation, esp one about to lose his or her job.

(Collins Dictionary)

The original AmE expression appears to have been coined in relation to death executions but it has probably an older history. Thomas Hardy wrote a poem in 1909 whose title was "The Dead Man Walking" where he used an expression which was probably already known at that time. Ngrams shows earlier usage instances but it is not clear where the expression comes from,( the spike in usage from the mid-90s is obviously due to the popular movie of the same name).

Questions:

• What's the origin of the expression 'dead man walking'? Could it have been taken from some religious writings for instance?

• When did the figurative informal usage first appear? Was it an AmE or a BrE extension of the more common expression?

I would distinguish between instances of "dead man walking" in the sense of "a man walking as if he were dead" and instances of the same phrase used in the sense of "man condemned or in some inescapable way doomed to die soon." Writers and speakers might use the phrase in the former sense in situations where the "dead man" is purposeless and joyless, but not necessarily headed for imminent death. Such a person might be a "dead man walking" for years.

In prison lingo, "dead man walking" seems initially to have referred to a condemned person walking to the place of execution. It may, however, have been broadened subsequently to apply to anyone living in prison under a death sentence. (I haven't found any information on this point.)

There is an interesting early instance of the wording used in the sense of "man doomed to die" (although not following conviction of a crime). From "A Soldier's Doom: The Horrible Result of a Bite from a Mad Horse," in the [Monmouth, Illinois] Warren County Democrat (January 17, 1895):

"Pooh, man, no danger, no danger!" the surgeon had said, as he dressed the wound.

"It's only a scratch, and we won't talk about it," the corporal made answer to all his comrades."

We had nothing more to say, except among ourselves, but from that hour every trooper in "C" company felt that Corporal Wallace was a doomed man, just as surely doomed as if a court-martial had sentenced him to death and the president had refused to interfere with the findings. You will say it was curious that we avoided him. So it was, and yet we could not but feel that he was a dead man walking about among us. We heard him speak, we saw him in apparent good health, we listened to his songs and stories at night, and yet every man who heard and saw and listened kept repeating over and over to himself:

"The corporal was bitten by a mad horse, and sooner or later he will go mad and die."

Somewhat similar is this instance from "Wife Slayer Says He's Already 'Dead Man'," in the Richmond [Kentucky] Daily Register (March 16, 1920):

Lexington, Ky., March 16—Declaring in answer to questions about himself that he is a "dead man walking on earth," Claude Lykins, who was brought to the county jail here for safe, keeping after it is alleged he killed his wife in Morgan county, would not discuss the crime of which he is charged.

Lykins asserts he has been dead for some time, but when he died of what cause or why he is permitted to remain on earth were questions to which he replied, "I don’t know."

But most relevant to the modern prison sense of "dead man walking" is this item in a "New Books" column in the [Kalamazoo, Michigan] Focus News (December 15, 1978):

DEAD MAN WALKING, W. Reason Campbell--the author's experiences teaching in a maximum-security prison.

Campbell's book, which is subtitled "Teaching in a Maximum Security Prison," seems to be mainly about the experience of being a teacher in that setting, rather than particularly involving work with condemned prisoners. Nevertheless, the usage cited in Robin Hamilton's answer is exactly on point. Here is a fuller version of the excerpt that appears in that answer [combined snippets]:

A student came up with a theme entitled: "Dead Man Walking." It described a scene he had witnessed in the yard at San Quentin. When a man on Death Row had to leave the compound containing the gas chamber for a court appearance, he had to walk across the yard, surrounded by six guards. The condemned man was dressed in brown, in contrast to the blue denim of conventional inmates. The condemned man walked with his head bowed as the loudspeaker boomed out repeatedly, "Clear the yard. Dead man walking. Dead man walking."

I encouraged students to develop their own writing projects, and if they got something going would excuse them from regular assignments.

From this excerpt, it appears that the slang phrase was already in use in the prison at San Quentin (California) by 1978. And if Campbell was writing about his teaching experiences at a different prison, the San Quentin incident may have been considerably earlier than 1978.

While there are examples of the phrase "dead man walking" from at least the nineteenth century onward, these are mostly in the form of a reference to spiritually dead (possibly ultimately from Paul's Epistle to the Ephesians) or the Zombie Syndrome. In neither case is there the sense of someone now alive about to be dead.

This particular variant of the expression emerges from the context of capital punishment in US prisons, either the gas chamber or the electric chair. The earliest reference I've found is in W. Reason Campbell, Dead Man Walking: Teaching in a Maximum-Security Prison (1979), Page 111, here:

The phrase is later used by Stephen King in The Green Mile (1996). Given King's popularity as a novelist, this may be part of the reason it is now widely current. (King's novel was where I first encountered it myself.)

Once the expression has become established in its Death Row form, it's unsurprising that it develops an extended metaphorical sense to refer to figures (usually politicians) whose future is insecure.

The current figure metaphorically walking the green mile is, of course, Theresa May whose future, either as leader of the UK Conservative Party, or as British Prime Minister, is ... uncertain.

Yes, it is originally from a religious writing.

The oldest example I see is in a 1765 English translation of The philosophical dictionary for the pocket, defining the word "miracle":

An eclipse of the sun and moon, a dead man walking two leagues with his head in his, hands, are what we call a miracle

Then from The Works of Thomas Goodwin, Volume 2 (1861)

if a dead man appear, walking ; it would affright us all to see a dead man walking ; yet, you see, dead men here are said to walk

The author is discussing Ephesians 2:1-2:

...who were dead in trespasses and sins;...ye walked according to the course of this world...

Just a year later; however, is a non-religious use in A Drawn Game Harper's Magazine (March 1862):

I broke my mother's heart. I have ruined myself. I am a dead man walking!

Certainly the origin of the more common contemporary US sense and use of the phrase 'dead man walking' must be understood in the context of all forms, senses and uses of the phrase, current and historical.

Among the forms of the phrase, I include these:

• dedman/dedeman/deadman/dead man walk/walks/walked/walking
• inverted and plural forms of the previous (for example, 'walking dead men')
• Deadman's Walk

Many of these forms are scarce or nonexistent in the textual evidence readily available for examination, and so were relatively easily assessed with an eye to their influence on the development and use of the common US phrase.

The spelling variants 'dedman' and 'dedeman' were suggested by early attestations (a 1400, c 1440) given with the entry for "deadman, n." in OED:

(deadman). = dead man: formerly written and pronounced as one word. (Cf. blindman n.) Obs. exc. in names, as Deadman's Walk.

Fortunately for what little remains of my sanity, forms of the phrase using the early spellings ('dedman', 'dedeman') were nonexistent in full-view works in the HathiTrust Digital Library corpus.

Three senses and use-contexts of the phrase, current and historical, are especially pertinent in light of the question asked. Those have already been mentioned in the question, but for clarity I'll reiterate them, slightly reworked and elaborated, here:

1. Religious senses and contexts. It was suggested that religious writings might be the origin of the phrase.
2. In the US and South Africa, and especially in the context of use in US prisons, the phrase is reputed to be or have been used to announce or otherwise refer to "a condemned man walking from his prison cell to a place of execution" (Farlex Dictionary of Idioms, 2015, and Collins English Dictionary, 2017).
3. In general, common and informal contexts, by "extension", the phrase is used to refer to "any man who is in great trouble or difficulty and is certain to face punishment, especially the loss of a job" (op. cit.).

The form "Deadman's Walk" could be dispensed with out of hand, were it not for the following historical account concerning Oxford and environs, published in the Oxford Journal, 13 February 1886 (paywalled):

"Over against Logic-lane," says Wood, "there was a way through Alban Hall Walkes, where yet in the towne wall is the signe of a doore to goe into the meade." Here and there are still to be seen the crowns of the arches upon which the wall hereabouts was built, and on the south side of the wall is that sheltered retreat from which it is said to have derived its name of Deadman's Walk. I was informed, however, by the late General Rigaud that the walk acquired that name in consequence of the execution of Col. Windebank, who was shot under the Merton wall for surrendering Blechingdon House to the Parliament forces. On the other hand the late Mr. Davenport says Col. Windebank was shot within the precincts of the Castle. I have searched the pages of Rushworth as the most probable author in an attempt to clear this discrepancy, but in vain, and I must leave the task to others.

As is apparent from the account of General Rigaud, supposing it to be true, Col. Windebank could be said to be the prototype 'dead man walking' to his place of execution, an event which is memorialized in the name of the walkway itself. Whether or not this event or the name of the walk in any way influenced the later development of context-sense 2 (above) in the US and South Africa, the name of the walk at least demonstrates that the essential semantic and collocative elements of the phrase, that is, essential elements of the phrase's origin, were already in use when Deadman's Walk was named, presumably sometime in the late 1600s or early 1700s.

Use of forms of the phrase in religious contexts appears at least as early as 1654. Such uses as precursors of context-sense 2, the contemporary US-South African sense, seem to offer little more than demonstration that the collocation has been in use for centuries. As precursors of a generalized context-sense 3, 'a man in great trouble or difficulty certain to face punishment', the lineage seems more exact and pertinent, as will be shown in the examples of forms of the phrase in religious contexts.

It should be noted at this juncture, however, that context-sense 2, 'a man facing execution' is itself a highly specific and distilled version of the generalized context-sense 3, 'a man in great trouble or difficulty certain to face punishment'. In consequence, I would expect to find examples of the general sense (3) in use, and applied in a variety of contexts, before the development of context-sense 2, and this was the case. Among those examples are early uses of the phrase in religious contexts.

5. Where you say that [without faith a man can no more Receive Christ, nor do ought towards it, then a dead man can walk or speak.]....
6. That [without faith, such can no more do ought towards the receiving of Christ, then a dead man can walk or speak]....

Rich. Baxters apology against the modest exceptions of Mr T. Blake, 1654.

In the example given, a clear figurative parallel between the troublesome plight of a man without faith and a dead man walking (or speaking) is drawn. Again, the essential semantic and collocative elements of the phrase 'dead man walking' (context-senses 2 and 3) have been deployed. So also in the next example from a religious context, although here connection between the troubled melancholic and certain punishment is not so clearly drawn:

The Sanguine man tels the Melancholick of faction, separation and pride, and sayes he is like the Pharisee, that justified himself and despised others. He tels him, his name is Stand farther off, which saith, because he thinks that he is holier then others. He accuseth him of malice and spitefulness, and faith, that Love is much decayed, since these pure Gospellers came up. He hates him as the Enemy of Mirth, yea the enemy of Life, for he holds him a walking dead-man, and doubts he seeks to make others as dead as himself.

Treatises and meditations, dedicated to the saints, and to the excellent throughout the three nations, Francis Rous, 1657 (emphasis mine).

Moving from the grandeurs of religion and capital punishment of the soul or its corporeal vessel to the trivia of personal finance, the evidence shows aphoristic use of the phrase 'dead man walking' before the development of context-sense 2, rather than after it. After was indicated by the Collins reference to "by extension" for the "general, common and informal" sense "any man who is in great trouble or difficulty and is certain to face punishment, especially the loss of a job" (emphasis added), yet these uses were earlier:

All the rest of the world went mad; but I went on quietly, creating confidence and credit — a man's best fortune in life, which, once lost, can never be recovered, and which, in business life, is better than goodness — yea, even than life itself; for it is the breath of a business man's nostrils, and without it he is but like a dead man walking.

John Horsleydown; or, The confessions of a thief, Thomas Littleton Holt and Hablot Knight Browne, 1860 (emphasis mine).

"Perdio," added his companion, "a man with money is a man in the right. So put that in your pipe, amico mio, and smoke it. Ay, money, it's like one's other blood; a man with empty pocket, 't is but a dead man walking."

Vestigia, George Fleming, 1884 (bold emphasis mine).

Finally, consider this 1919 account from a man with a view from inside:

The true House of the Dead is an English jail. There to give a crust of bread to a fellow or pass a word of cheer are crimes. Prisons, as I have said before, are not houses, they are sepulchres. Dead men walk in them, with expressionless masks of death on their faces, and silence, the brother of death, on their lips.

A second chronicle of jails, Darrell Figgis, 1919 (emphasis mine).

It's true, of course; prisons are a form of death in life, and prisoners are dead men walking, whether or not they are on their way to execution.