The Oocca are definitely one of the strangest new races ever introduced into the Legend of Zelda series. Their very existence has confused and angered fans. From their odd appearance to the claims of their great power, they are one of the more love it or hate it additions to the series. This dislike of the Oocca seems to come from a misunderstanding that I hope to rectify with this article.
Before I do anything else I'll show you the legend of the Oocca as stated by Shad in Twilight Princess.
What most people seem to gather from this that the Oocca somehow physically created the Hylian people, which would make the Oocca a vastly superior race. Needless to say that doesn't usually go over well, and people either dismiss it as a rumor or outright deny it. What I hope to do is explain the role of the Oocca by analyzing this legend, which is the cause of most of the confusion.
The legend starts out simple enough. Hyrule being made by the Hylians most likely refers to whenever the Kingdom was first established, as the Hylians couldn't possibly have shaped the land itself. It could be referring to the events preceding Ocarina of Time, with the king unifying the country, or it could be something else. Its not important because it's not in dispute here. Now for the closeness to the Gods, I believe that stems back to A Link to the Past with this quote from the manual.
So what I take from this is that the Hylian's "Closeness to the Gods" is shown by their ability to hear messages from the Gods and their ability to use magic. This earned them a great amount of respect from other races which eventually translated to the Hylians believing themselves better then the other races, or "Closer to the Gods".
Now we actually get to the Oocca. Now assuming what I established earlier as what "Closeness to the Gods" is was true, this is easily explained. The Oocca are arguably the most technology advanced race encountered in a Zelda game to date. This is demonstrated in two main ways: the City in the Sky and the Dominion Rod. The City in the Sky seems to harness the power of the winds to stay aloft indefinitely, while the Dominion rod breathes life into inanimate stone (this may or may not be magic, but as it is still very advanced, I'll use it). It is also very possible that the Spinner is of their design, as Spinner based machines are found in the City in the Sky. This use of technology is in stark contrast to the more primitive Hylian people.
The Hylia, being a race based on religion and magic, would judge anything or anyone they came into contact with based on these. The high technology of the Oocca would appear to be a very advanced magic. Now if they assumed the race which had the most powerful magic was closest to the Gods, then the Oocca would be the most obvious choice to fill that role.
Now we get to the part that causes some people to hate the Oocca. I'd like to point out something first, notice how its says "some" people make this claim. This makes it seem like, within the realm of the game, this is only someone's theory, and not a proven fact. However I will assume there are grounds to this theory and give two possible explanations.
The first concerns the Dominion Rod. As I stated earlier and as shown in the game this device is able to give inanimate objects what seems to be life. To anybody witnessing this rod being wielded it would appear that the user was able to breath life into the lifeless stone. Its not too great a leap from that to believing someone has the god-like power to create life. From there it would only take a simple misunderstanding to make someone believe the Oocca could have given life to the Hylians.
The second theory (and far more plausible to me) is that the Oocca helped create the Hylian Kingdom, rather then the race itself. It is stated by Impaz that the Oocca and the Hylian Royalty used to keep in contact with each other.
Seeing as we know the Oocca shared their technology with the Hylians (Dominion Rod, Clawshot, and possibly the Spinner) I think its safe to assume that they would have used their abilities to help the Hylian royalty. An example of this help could be in construction, as the Oocca seem to excel at building despite their physical limitations. Evidence for this can be seen in the presence of Spinner-based objects (machines, walls, respectively) in both the City in the Sky and in Hyrule Castle. With the knowledge of the Oocca to aid them, it would have been easier for the royal family to unify the tribes and found the Kingdom of Hyrule, the seat of Hylian power.
This obviously refers to the creation of the City in the Sky. In order to maintain contact with the Hylians from their city, they would have most likely used the Messenger of the Heavens (the role you take up in Twilight Princess), and as they gave the messenger the Dominion Rod, it further supports my theory of them sharing technology. Also supporting the theory is that it says they both created the Hylia and built their city simultaneously, which means they would have had to communicate through the messenger, who reported to the royal family.
So this places the "creation" of the Hylia and the founding of the kingdom (as a royal family can only be royal if they rule over a country) at about the same time. We know that Hyrule was founded after the Hylia came into being by common sense, and by this quote of the Deku Tree Sprout from Ocarina of Time.
So this shows that the creation of the Hylia was awhile before the founding of Hyrule, meaning the Oocca couldn't have created the Hylia as a people, but could have help founded the Hylian nation.
So from what I've established here the history of the Oocca in relation to the Hylian people go as follows. First the Gods create the world, then they create life, more importantly to this topic the Oocca and the Hylians (the Oocca could have been made first as they seem to have had time to advance). The Oocca live separately from the other races, away from what would become Hyrule. The Oocca then establish a connection with the Hylians, more specifically the royal family, through the Messenger of the Heavens. The Hylians use this knowledge to unify and found Hyrule, while at the same time the Oocca create and dwell in the City in the Sky. The royal family maintain contact with them until the knowledge of how to is lost. Time passes until the events of Twilight Princess, where contact is made again
So I hope this clears up some misconceptions about the Oocca. They are not some all-powerful race who created the Hylians, they are simply allies of the royal family who helped found Hyrule. This way the previous history given in other games is not overridden, but added to. The Oocca remain an odd, hidden, but very influential part of Hylian history.