VARIANT TRADITIONS & WHATNOT
There were various different traditions from the myriad ethnic groups of ancient Greece, a lot of which traditions were influenced by neighbouring cultures. The different mythographers - i.e., the guys who recorded these myths which are the source material from which we read them today - interpreted these different traditions in different ways as best they understood them, because often it was confusing even to them. The mythology of Greece itself is sort of a mishmash of stuff inherited or borrowed from Mesopotamia, northern Africa and most likely India too, and if you've read even a few of the myths of those places, they're like 22 times more confusing than almost any Greco-Roman myth.
Interestingly a few of the mythographers did not believe the more “fantastical” elements of their own people’s myths and so sought to either explain them away as allegories for or exaggerations of more “realistic” events using their own ingenuity (like Euhemeros, who did this to the extent that, from his name, this method/process of rationalising myths and legends is called euhemerism), or they simply paid more attention to the less fantastical traditions than those which were more so (like the traveller Pausanias did). Pausanias notes the phenomenon of numerous traditions when he writes about Zeus’ birthplace, saying that “It is a hopeless task, however zealously undertaken, to enumerate all the peoples who claim that Zeus was born and brought up among them.”
To sort through the thick forest of duplicated names & multiple versions of most characters of the mythology, I’ve personally found these sites to be extremely helpful as primers (since they catalogue the personages and events quite neatly and tidily but also keep things basic while satisfactorily detailed at the same time):
http://www.maicar.com/GML/index.html
http://www.mythindex.com/
An often helpful companion to these is Wikipedia http://en.wikipedia.org/wiki/Greek_mythology although beware: I’ve found incorrect information 1 or 2 times in the separate articles on individual characters. The articles, however, are often very good with referencing the exact source materials from which the information they contain is derived.
And if you really want to go into crazy detail, with extensive quotes of the original mythographers, translated into English, of course you’ll want to go here: http://www.theoi.com
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CHRONOLOGY
In spite of the multiplicity of traditions, versions and accounts, and arguments for or against each one depending who was writing or talking about them, Greco-Roman mythology does have its own rather tightly-woven internal chronology, even taking into account the few characters who would need to have gone through a time-warp to exist in the eras in which they are said to have lived. Here are some breakdowns of the timeline of these myths, based on medieval and modern interpretations of which period in history the events of the mythology would have happened if they did:
http://www.maicar.com/GML/MythicalChronology.html
http://www.personal.utulsa.edu/~marc-carlson/history/clam.html
http://www.argyrou.eclipse.co.uk/Myths2.htm
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BIRTHS, DETHRONEMENTS & MORE BIRTHS
Concerning the events you’ve asked about specifically, this is how things went down:
The first twelve Titans, the three Cyclopes and the three Hekatonkheires were born. Fearful of them, their father Ouranos (the Sky) shoved them back into their mother’s womb, preventing their full emergence. In her pain, their mother Gaia (the Earth) conspired with the Titans against Ouranos, giving a cosmic-sized sickle to Kronos, the youngest Titan and the one most eager to lash out against his father. Kronos did *not* cut Ouranos to pieces. He only castrated him. The other Titans, with the exception of Okeanos, helped their brother by stretching their father’s limbs out. This action separated Sky from Earth.
Just as fearful of his younger brothers, the Cyclopes and the Hekatonkheires, as their father had been, Kronos imprisoned them in Tartaros, the deepest part of the Underworld. Kronos also threw Ouranos’ severed genitalia into the Sea. As Ouranos was rising off the Earth, thus allowing his eighteen children to finally be born, the Sky-god cursed Kronos saying that he too would be overthrown by his own offspring. This is the reason that Kronos became fearful of his own children and swallowed them at birth. The Titans’ War did not happen until some time later, after Zeus, the youngest child of Kronos and Rhea, had grown up and tricked his father into vomiting the older offspring whom he had earlier swallowed.
Most of the younger Titans (Zeus’ cousins and the kids and grandkids of these cousins) then flocked to Zeus’ camp to do battle against their own fathers, uncles and grandfathers, and there was war which raged for nine years, apparently in the Plain of Thessalia [Thessaly]. Neither side made much progress against the other until Zeus released his uncles, the Cyclopes and the Hekatonkheires, from Tartaros, and with their additional help Zeus won the war and cast Kronos into Tartaros.
In the meantime, Ouranos genitals, which had landed in the Sea years before, had now mixed with the salt and foam therein, forming the beautiful goddess Aphrodite. She spent the first many years of her life in the Sea, where she was reared by the marine nymphs. Courtesy of Diodoros of Sicily, we can deduce that she spent the entire duration of the Titans’ War in the Sea, perhaps never having met any of the Olympians whose group she would eventually join. Diodoros says that “at the time when Zeus is said to have subdued the Titans” he and a Rhodian nymph called Himalia had three sons named Spartaios, Kronios and Kytos. When these guys were still young men, their unnamed cousins, the six sons of Poseidon whom you’ve mentioned, lived on the same island, and it was at that time that Aphrodite first came to Rhodes.
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SO SOME MORE CHRONOLOGY
With this information we can construct a nicely plausible timeline, even using short, humanly normal timeframes:
- Sometime in between 42,000 & 32,000 BC, Kronos castrates Ouranos and casts the severed member into the Sea.
- 3 years later Kronos and his wife Rhea have had 6 children, all of whom have been swallowed, with the exception of Zeus whom Rhea has managed to hide away from his father.
- 20 years later Zeus tricks Kronos into vomiting the 5 older children, who are Zeus’ older siblings.
- 1 year later the Titans’ War begins.
- 9 years pass and the war ends in Kronos’ defeat. In the same year, on an unnamed Aegean island, both Zeus and Poseidon have children. Zeus has 3 sons with Himalia while Poseidon has 6 sons and 1 daughter with Halia.
- 20 years later Poseidon’s sons name the island Rhodes after their sister Rhodos. In the same year, Aphrodite tries to put in anchor upon passing by the island but she is rebuffed by the Rhodians. Consequences follow, which is another story.
Tallying that all up, it = 53 years from the time of Ouranos’ castration up to Aphrodite’s emergence from the Sea (or her “birth” as it is often, perhaps misleadingly, called). I don’t think it’s mentioned anywhere how long it took for Ouranos’ severed member to metamorphose into a beautiful goddess. It could have taken 26 years so that she thereafter spent 27 years growing up in the Sea, or it could’ve been 9 months so that she was just over 52 when she first appeared on dry land… but then again what difference would such an amount of time make to an immortal entity?
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THIS “DEMIGOD” THING…
As for your final question, the use of the term “demigod” here is particularly problematic, especially with the modern pop culture misinterpretation or oversimplification thereof, I mean in a manner in which the ancient Greeks (and Romans) would barely have understood or used the designation. There are many characters in the original mythology who were the children of a god and a nymph, or would have been the mortal offspring of two immortals. Do these ones qualify as “demigods” to you? If the sons of Zeus and Himalia, and those of Poseidon and Halia, count as demigods, then, incidentally they are the only such children of gods who were born around the time of the Titans’ War that I’ve encountered in Greek myth.
Since you’ve asked specifically about children being had *during* the war, however, for these guys to fit into that 9-year time-slot, we’d have to interpret the line “at the time when Zeus is said to have subdued the Titans” to mean “at the time when Zeus is said to have still been in the process of subduing the Titans” (i.e., while the war was still ongoing)… which I doubt is the meaning actually intended by Diodoros here.
So maybe a shorter and more straightforward answer to that last question is: No, there doesn’t appear to be any instance of the gods having any such children during the war against Kronos.
NB: About Spartaios, Kronios and Kytos: They don’t seem to be mentioned anywhere else, and beyond their location and their description as “young men,” Diodoros never tells us what exactly they were. The same passage may be suggesting that they were giants but whether mortal or immortal is hard to say. We also don’t know what kind of nymph their mother Himalia was; we know there were many varieties of nymph, some of whom were immortal goddesses (like Rhodos) while others were mortal, almost human creatures (like Rhodos' mother Halia seems to have been). In fact the term “demigod” is more accurately applicable to nymphs as opposed to the currently popular use of the same.