I just stumbled over the verb "to wake", which according to various sources has two valid forms for the past tense: "woke" and "waked".
Some further research stated, that there seem to be two (Old / Middle) English verbs - one strong, one weak - today's "wake" stems from, hence the two forms for past tense:
Now, as there are two origins, I'm wondering:
Are there (subtle?) differences in meaning when using "woke" or "waked" today?
This is rather a knotty little group of verbs that have gone all over the place in Modern English, though they were very clearly and regularly distinguished in Old English.
Let’s start with the etymology, and then move on to current usage.
The words watch, (a)wake, (a)waken all share a common root. The Proto-Indo-European root was *u̯eǵ-, and its basic meaning approximately ‘to be strong/quick/lively/aroused/powerful’. It underlies for example Sanskrit वाजः vā́ jaḥ ‘power/force’, Latin vigil ‘watchful/awake’ (as in English vigil also), vigere ‘be lively’ (as in vigorous in English), velox ‘fast/lively’ (from *veg-lox; as in velocity in English).
In Proto-Germanic, the root regularly became *wek-, with the ablaut form *wak-. This latter form generally took over, because it was found in a very common construction with this root: the causative (PIE) *u̯oǵ-ei̯e- > (PG) *wak-ja- ‘make lively’ = ‘awaken [someone], wake [someone] up’. So for all practical purposes, the Germanic root was *wak-.
There were then at least three different verbs derived straight from this root present in Proto-Germanic (note: *-aną- is the reconstructed Proto-Germanic infinitive marker):
These were all quite regular, since both the causatives and inchoatives were regularly formed in Germanic by adding the *-j- and *-n- suffixes.
In Old English, they were also relatively distinct, although some parts of the paradigms had already started to coalesce. Most notably, both the old base verb and the old inchoative verb had become strong verbs in verbal class VI. This is original to the base verb (which is a primary, non-derived verb and therefore shows ablaut—the Proto-Indo-European equivalent of Germanic strong verbs), but not to the inchoative verb. The inchoative verb is a derived one, and it ought to have been weak; but it had fallen together with the base verb in the past tense.
This coalescence is very clear if you look at the Wiktionary paradigms for Old English wacan and Old English wæcnan: the past tense forms are the same, the others are distinct.
The causative *wak-j-aną-, on the other hand, had maintained its different conjugation throughout: it remained a weak verb of class II, Old English wacian.
So at a brief glance, if we give just the third person singular of the three verbs in Old English:
In Middle English, when final syllables started being reduced and lost, the differences between these three paradigms started getting muddled. The Middle English infinitive forms are the ones you have found on Wiktionary yourself:
Once the forms started getting muddled, obviously the meanings started to overlap—it’s difficult, after all, to maintain a difference between ‘becoming [by one’s own accord] awake’ and ‘causing [someone] to be awake’ and ‘being awake’ when half of them have the same shape in various forms in the paradigm.
In current English, there are only two basic forms left: wake and waken.
Wake is, in form, basically from the old base verb waken < wacan. The modern verb waken, on the other hand, is from the inchoative waknen < wæcnan. Note that in both these words, it is the final -en that has been lost over time, and modern waken thus represents Middle English wakn, to which of course an extra little prop vowel was added, since /kn/ is not a valid way to end a syllable in English.
In Middle English (as in Old English), both waken and waknen generally had a strong past form, wook (in various spellings), which is what gives modern woke. The weak causative wakien had a weak past, waked(e). When the form of the causative was mostly lost (merging with the base verb once -en disappeared), the weak past was kept in some dialects, the strong past in others, and both in yet others.
On the other hand, the inchoative waknen developed a new weak past of its own, wakned(e) and stopped using wook like the base/causative verb. So there was a shift in what verbs shared what past tense forms:
This is the reason why waken today has only a weak past form, wakened, while wake can have both strong woke2 and weak waked.
When the causative disappeared as a separate form, the rather unusual thing happened that its semantics were taken over not only by the base verb (with which it merged in form), but also by the inchoative verb. This means that both the base verb and the inchoative verb can now be either transitive or intransitive, which is a messy situation, but reality.
In current English, woke is the standard past tense of wake, both transitive and intransitive, causative or not; waked is marked as nonstandard (dialectical) or archaic, and it’s nowhere near as common as woke.
An exception to this is when wake is not the inherited verb(s) discussed above, but rather a different verb derived (through normal zero-derivation) from a noun. Wake as a noun has at least two common meanings (etymologically unrelated): a vigil after the death of someone; and the trail of water or air left behind a vessel. When either of these nouns is used as a verb, the verb is a secondary, derived one, and such verbs are (nearly) always weak.
That means that the local community waked old Mrs. Smith last week after she passed away; you would never say that they *woke her. Similarly, you might possibly say that the ferry waked its way through the narrow strait; but certainly never in a million years that it *woke its way.
(Thanks to @supercat for mentioning this in the comments below.)
1 There’s quite a bit of discussion about what the exact usage of these nasal formations were in Common Germanic. They are often based on nouns describing people or jobs, and they then mean ‘do/behave as X does’, a basically causative or factitive meaning; thus, in Old English, we get læcnian ‘heal’ from lǣċe ‘doctor’. But they are also used more or less as inchoatives from adjectives, as blacken ‘become black’ from black.
2 As Jon mentions both in his answer and a comment here, woke, phonemically /woʊk/, is not quite regular from the Old English wóc. Some analogy with similar-sounding verbs like break, speak, and steal (which did sound the same earlier on, though they’re different now) took place at some point. Middle English wook or wooke or woke can be regular from wóc, assuming that they represent /wuk/, which is what the Old English form should give—but that’s not necessarily a given, considering the vagaries of Middle English spelling.
Garner’s Usage Tip of the Day: Miscellaneous Entries. seems to indicate that the preferred choice between the alternative forms of the past participles 'waked' and 'woken' is determined purely geographically. It is probable that the choice of past simple reflects this to a limited degree, though Garner does not list 'waked' as a 'preferred' choice:
wake; awake; awaken.
The past-tense and past-participial forms of “wake” and its various siblings are perhaps the most vexing in the language. Following are the preferred declensions:
“wake / woke / waked (or woken)”;
“awake / awoke / awaked (or awoken)”;
“awaken / awakened / awakened”;
“wake up / woke up / waked up.”
For the past participle, American English prefers “waked”; British English prefers “woken.”
The erroneous claim that 'waked' is not an acceptable past participle of 'wake', by a 'senior member' (sound shift) at WordReference.co, shows that the acceptability / idiomaticity of the usages of these verbs cause quite a lot of disagreement.
Another senior member there (morior_invictus) (and I thought the usernames here were outlandish) says:
I have seen "waked" as the past tense of "wake" in American English, but "I have just waked up." sounds incorrect to me as well.
I would accept "I just woke up." (i.e. a simple past) or "I just waked someone up." but not "I just waked up." It doesn't sound good to me.
I agree that transitive vs intransitive usage makes a difference to idiomaticity, perhaps even acceptability. The US - UK divide is also an important factor.
Some further research stated, that there seem to be two (Old / Middle) English verbs - one strong, one weak - today's "wake" stems from, hence the two forms for past tense:
This appears to be irrelevant, but that it is is actually more interesting than if it isn't, because we'd actually expect this dual-form to happen here, because wæcnan was a strong verb and wacian a weak verb.
"Strong verb" would mean the sort of verb that has the woke and woken forms, with the sort of verb that has a waked form being correspondingly referred to as a "weak verb". This use of strong and weak coming from Jacob Grimm's writings on Germanic languages (including English).
So, all things being equal, we'd not be surprised at this dual form. Notably, the OED tells us:
In Middle English the strong and weak forms came to be used indiscriminately in both senses.
So, at this point there were two ways of saying the verb in the past tense, but no semantic difference between them.
However, the OED claims:
The modern past tense woke /wəʊk/ does not regularly represent the Old English wóc , which would have yielded wook /wʊk/ . Apparently the modern woke is a new formation or modification on the analogy of broke , spoke (for the irregularity in the vowel compare stove past tense of stave v.). When this came in is uncertain, for in Middle English and probably in early modern English the spelling woke represents the regular phonetic descendant of the Old English wóc. The past participle waken has always been rare, and now survives only in dialects in adjectival use. From the 17th cent. onwards the forms woke, woken (after broke, broken, spoke, spoken, etc.) have been more or less current for the past participle; woke seems obsolescent, but woken is at least as frequent as waked. No strong forms either of past tense or participle are found in Shakespeare, the Bible of 1611, or Milton's verse.
So there was a woke that was more like wook, but it died out to leave waked, but then people produced a woke by analogy to how the rhyming break has a broke.
Indeed, we can see a suggestion of this wook form in the spelling used in:
Grete lordes riste toke, & nyghte wache full worthily wooke. — Duke Rowland and Sir Otuell ca 1400
For a strong verb to become a weak one (that is, to become one that we use -ed with) is very common. A lot of our current weak verbs were strong verbs in Old English. This is understandable since we all know the general rule about adding -ed to a verb, but have to learn the other forms, not least because they've become increasingly irregular over the centuries. It's not hard to see how people would apply -ed to verbs that previously did not take it, and that would eventually become the form everyone used.
For a weak verb to become strong is less common, but does still often happen. This answer has more information on that.
This claim by the OED would explain the history of use we can see here:
As always, take ngrams with a pinch of salt (and alas they become almost completely useless once you go back another century which is where we would most want to see the history), but it does amount to additional evidence.
So if you'd asked this question five hundred years ago, the answer would indeed have been "because there are two source Old English words", but in since then the verb has managed to first lose one of its past-tense forms, and then later acquire another!
Are there (subtle?) differences in meaning when using "woke" or "waked" today?
As noted in the answer I linked to, sometimes when we have this dual-past phenomenon one of them becomes more heavily used in some senses.
Here, of those senses that relate to keeping a watch waked remains more common, while woke is more common in terms of transitioning from sleep to wakefulness.
The sense about stopping sleeping is in itself much more common than the other senses anyway, and hence woke more common generally, but in areas where it is still common to say that you waked someone as in you hosted or attended their wake after they died (a sense now mostly only found in Ireland though still sometimes found in Scotland and England, particularly the north) it would be very unusual to use woke while for a living person whose sleep you disturbed woke would be more common but waked would still be heard.
That the sense I just mentioned is rare in most of the English-speaking world is likely relevant. To quote the OED again:
but in the modern English period the static sense, both intransitive and transitive, has become almost obsolete, the usual meanings of the word being ‘to become or cause to become awake’.
It is likely precisely because these senses are now rare or even archaic in most dialects that one does not use the more recent woke with them; in most dialects it would only be used in a deliberately old-fashioned manner, and in the few remaining other cases it just didn't acquire this new woke in that sense.
This distinction is not so sharp as to be anything close to "a rule", again because the relative rarity of these other senses today would prevent a strong sense of "this is the correct way" emerging.
