The Swastika is a pretty basic geometric shape, and as such has been around in different parts of the world since the Neolithic. People have been making abstract scratchings on bone or rock for 70,000 years, and the Swastika, being a simple shape, is not hard to come by.

There are a couple caveats though. First, how closely does something have to resemble the modern Swastika before you call it a Swastika? Is something vaguely cross-like good enough to be called a Swastika? Depending on how loosely you define it, the oldest "Swastika" could be a scratching on a piece of bone from the Ukraine, which is 10,000 years old. Other archeologists think that's far fetched, it looks more like a cross than a Swastika, and is probably meant to represent a stork or some similar bird.

Secondly, we must consider frequency of use. Because it's such a simple shape, someone could scratch or carve it on rock by accident while doodling. It doesn't necessarily have any cultural or religious significance. In such cases, you'd expect to find rare incidences, and they won't be exactly alike. On the other hand, if you find lots of examples from some specific time and place, and they all look very similar, then you might think it was a symbol that had been "standardized" and held cultural or religious significance.

In that sense, the earliest example we have of standardized and repeated usage of the Swastika is from ancient India, the Indus Valley Civilization, about 5,000 years ago. You can see it on a great many clay seals such as this one, which were used to stamp the pattern on other objects. And it's found all over homes and objects in the Indus Valley. Clearly, it was something of significance to the people.

Hinduism is the oldest known religion to have used the Swastika. Hinduism arose in north India from the confluence of the beliefs and practices of the early Indo-European people, and shramanic traditions originating in the Indus Valley Civilization. The word "Swastika" is Sanskrit, meaning "lucky object".

From Hinduism, the use of the Swastika spread to Buddhism and Jainism, which were offshoots of Hinduism in the 5th century BC. Buddhism was transmitted to China from India during the Mauryan period (3rd century BC), and the symbol became popular in East Asia as well.

Hitler's use of the Swastika goes back to a few racialist writers in the late 19th century. Among the earliest mentions of north Europeans being touted as "Aryans" is from a Frenchman named Emile Burnouf, who wrote about racial theories describing the Aryans as naturally polytheists (while Semites were monotheists), and ascribing the glory of Ancient Greece, Rome, India to the Aryans. His ideas were very popular in Germany, where a number of societies and political movements were arising, based on the notion of racial purity. Alfred Rosenberg and several other German writers were spreading the idea that Germany could be great again if they were a racially pure and homogenous people. It also helped put the blame on other races, who had corrupted and harmed the German people.

So when Hitler was growing up, there were already many organizations in Germany based on theories of racial superiority, which claimed that Germans were Aryans, and used the Swastika (which was recognized in Europe as a symbol of the ancient Indo-Aryans) as their symbol. Hitler probably saw dozens of flags and logos using the Swastika to represent German racial superiority.

So when the time came for him to design his own party's flag, he picked the Swastika. It was a well-recognized symbol in Germany at the time, and would have quickly told the public what his party stood for.

The use of the Swastika in India (and among Hindus, Buddhists, Jains), has nothing to do with these European developments, and predates them by 5,000 years.

I don't quite understand the question. Could you clarify?