Wednesday's Random Slang-o-rama: Cry Uncle!

 How did Cry uncle! come to describe begging for mercy or waving the white flag? Why not cry (or say) brother? or aunt? or....?? And (my ever-present question for idioms and slang) when did it first come into common use?

Let's see if the internet has an answer or two.... 

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.. and of course, being the internet, it does!

Over at World Wide Words, a post on the origin of this idiom starts with "It’s always the shortest questions that take the longest to answer" and continues:

There has been a lot of speculation about this idiom. I am now able, as a result of help from several sources, to provide a clear pointer to where it comes from.

WWW notes that the earliest examples—dating from 1891 to about 1907— appear in the form of jokes. Here is one from the October 9, 1891 issue of the Iowa Citizen:

A gentleman was boasting that his parrot would repeat anything he told him. For example, he told him several times, before some friends, to say “Uncle,” but the parrot would not repeat it. In anger he seized the bird, and half-twisting his neck, said: “Say ‘uncle,’ you beggar!” and threw him into the fowl pen, in which he had ten prize fowls. Shortly afterward, thinking he had killed the parrot, he went to the pen. To his surprise he found nine of the fowls dead on the floor with their necks wrung, and the parrot standing on the tenth twisting his neck and screaming: “Say ‘uncle,’ you beggar! say uncle.’”

However, this doesn't answer the question as to why "uncle" is invoked. Ah, but the never next paragraph goes into that:

Later versions make the reason for choosing uncle as the key word clearer by starting the story “A man whose niece had coaxed him to buy her a parrot succeeded in getting a bird that was warranted a good talker.”

The post is a good one, and goes into some similarities/congruences between U.S. English and British English regarding this idiom.

The Facts on the File Encyclopedia of Word and Phrase Origins (Fourth Edition, 2008) by Robert Hendrickson puts the more abbreviated uncle! in common use in the early 20th century, adding, "Apparently it is of schoolboy origin, at least it is most used by schoolboys when fighting, especially when one has another pinned helplessly on the ground... Why uncle was chosen by kids is anybody's guess..."

But wait! The Word Detective opines that cry uncle has roots back to the Roman Empire (!!):

...Roman children, when beset by a bully, would be forced to say "Patrue, mi Patruissimo," or "Uncle, my best Uncle," in order to surrender and be freed. As to precisely "why" bullies force their victims to "cry uncle," opinions vary. It may be that the ritual is simply a way of making the victim call out for help from a grownup, thus proving his or her helplessness. Alternatively, it may have started as a way of forcing the victim to grant the bully a title of respect -- in Roman times, your father's brother was accorded nearly the same power and status as your father. The form of "uncle" used in the Latin phrase ("patrue") tends to support this theory, inasmuch as it specifically denoted your paternal uncle, as opposed to the brother of your mother ("avunculus"), who occupied a somewhat lower rung in patrilineal Roman society.  

Now that's a plot twist I did not expect in my investigation of this phrase...

A little hard to tell who might be crying uncle here.
A Man Interfering in a Street Fight, from Images of Spain Album (F), 82, (ca 1812-20) by Francisco de Goya
This file was donated to Wikimedia Commons as part of a project by the Metropolitan Museum of Art.
See the Image and Data Resources Open Access Policy, CC0, https://commons.wikimedia.org/w/index.php?curid=90333085

**** A tip o' the hat to amazing author and dear friend Camille Minichino who suggested this Slang-o-rama phrase!****