It was first used as an interjection in the 19th century: “They marched, and I amongst them, to face the enemy – heads up – step firm – thus it was – quick time – march!”
Then, at the beginning of the 20th century, it began to be used adjectivally, as in: “He was always right on the job, and looking ‘heads up’.”
Then, around the late 70s, it became a noun, probably through shortening of phrases like “heads-up alert” into “heads-up”: “It is regarded as being a heads-up on a sale.”
Source and references: the Grammarphobia blog
I cannot speak to its origin, but I can speak to the alleged redundancy. There is a reason it works as it does:
Every last one took their seat
The last one took their seat
Everyone took their seat
All three of these sentences mean slightly different things. Referring to only the last one you could be talking about one person. Referring to everyone is too generic and, in usage, it doesn't necessarily mean every single one:
The class will start when everyone is seated
Even after saying such, it is entirely plausible for the class to start before one or two stragglers get seated. By saying every last one, it is clear that every person must be seated.
This also holds for the usage akin to, "The strawberries were tasty; I ate every last one." This implies a much more thorough version of all of them. Plausibly, someone else could have eaten a few or you threw one of the nasty ones away. Using every last one works to reenforce the tastiness of the strawberries and the fact that I singlehandedly ate them all.
There are other phrases that work the same way:
Every single one
Each and every one
These have their own connotations — and avoid the confusion of every last — but they do not fully replace the connotations of every last one. Putting last in the phrase is very powerful.
(The rest of this answer is not terribly important.)
The phrase also has the advantage that it is three short words with a 2-1-1 syllable count. You can verbally morph this structure to emphasize the fact that they are all gone. Every single one is 2-2-1 which is workable, but doesn't quite have the same fast-slow-slow feel to it. More options are good things when it comes to timing and delivery.
This is commonly written by using periods after every word:
I ate every. Last. One.
I personally dislike this style but noticed that advertising from the last decade or two seems fond of it.
Best Answer
The short answer is that cursing is much closer to being universal than the way you portray it in your question, and English is not by any means unique in its handling of taboo. The subject matter may differ (though a huge number of different cultures seem to incorporate a few fundamental taboo concepts over and over again), but the function and ubiquity of curse words occurs in every society, including Japan. From Jay (2009):
I don't know enough Japanese to actually weigh in with my own opinion, but I understand that the idea that Japanese doesn't have "bad words" is a myth. Here is a group a reader-submitted anecdotes, many of which touch on Japanese curse words. While claims of "this language has no curse words/only one curse word" are very secondhand, I assume most of the specific references to Japanese curse words are not made up (someone with better knowledge of Japanese can weigh in there).
Cursing itself is such a fundamental act, many consider it to be extra-linguistic; from Fitch (2010):
Swear words seem to be some of the few words that can operate in ways that violate fundamental rules of syntax, as well. For example, we can say "what the fuck" or "what the hell", which, grammatically, makes no sense. Dong (2007) illustrates in much more detail (and yes, this was published under a pseudonym) that fuck violates many syntactic rules in unique ways.
The function of cursing might well be to alleviate stress or pain.
Taboo words evolve in a number of ways: over time, a specific word can lose its strength, but also, shifts in taboos and the severity of taboos can have a huge impact on the severity of a curse word. For example, bastard was a much stronger curse centuries ago than it is today. On the other hand, the recent development of e.g. retard into a curse word is reflective of the shifting attitudes towards the mentally challenged (i.e. how belittling/dehumanizing them has become taboo).
So, regarding your question of whether English was always this way: I think most linguists, neuroscientists, and psychologists would say that language seems to have always been this way. I'm not sure what you mean about English curse words being segregated into a fixed group. There are a lot of ambiguities surrounding English curse words.