Lemmygrad is wrong about a lot of things, but they're not wrong about this. It's important to learn from the past so it does not keep repeating.

The concept of the "white race" was developed in the 17th century with the Atlantic slave trade. It is indeed a product of British colonization. The concept literally didn't exist before this. Before the 17th century, people who we would now think of as white identified mainly by nationality and religion.

The concept of whiteness as being a distinct and unifying factor among people from a variety of countries led to the field of scientific racism, which went on for around 2 centuries. This is where terms like "Caucasian" came from. Scientific racism was used as a reason by the Nazis to murder millions of Jews. Now in the 21st century, we know it is pseudoscience even though its terminology lingers.

This doesn't mean that people were blind to skin color before 17th century colonialism, as you pointed out with the Indian caste system that dates back as far as 3300BC. You can see in ancient Egyptian art a wide array of colored skin as well. From Egyptian literature, there aren't signs they really obsessed over it the way society does now.

I think we can all agree that things didn't go too well for non-white people after the invention of whiteness. The concept was founded in oppression and helps perpetuate oppression.

Why not block the instance?

They may be a tankie but they’re not wrong that modern concept of race was invented as a part of the European slave trade and colonialism. I don’t think the United States has ever adequately reckoned with that fact as evidenced by this Karen Komittee crying about a fucking poster.

I'll make this one easy for you. The Guardian is a garbage white supremacist liberal rag that does the bidding of North Atlantic imperialists. But here's a shit article they wrote that explains this particular thing: https://www.theguardian.com/news/2021/apr/20/the-invention-of-whiteness-long-history-dangerous-idea

Here's the subtitle: "Before the 17th century, people did not think of themselves as belonging to something called the white race. But once the idea was invented, it quickly began to reshape the modern world"

That's right. There was no such thing as the white race until the 1600s. And here's the relevant excerpt:

[...] the plantation owners initially sought to protect themselves by giving their “Christian” servants legal privileges not available to their enslaved “Negroes”. The idea was to buy off the allegiance of indentured Europeans with a set of entitlements that, however meagre, set them above enslaved Africans. Toward the end of the 17th century, this scheme witnessed a significant shift: many of the laws that regulated slave and servant behaviour – the 1681 Servant Act in Jamaica, for example, which was later copied for use in South Carolina – began to describe the privileged class as “whites” and not as “Christians”.

Whiteness, white supremacy, was invented in the new settler state that became the USA. It was an extension of European supremacy and part of the liberalization process that was occurring throughout Europe as the "age of discovery" began lifting the merchant class into positions of power. This new financial class sought new social forms that would allow them to supplant kings while still maintaining the power structures they needed to continue extending their dominance across the world. Since kings were kings by divine right, they were literally working against a social fiction that required them to attack religion, which was impossible, so they needed new systems that directed power away from religious explanations. They needed to maintain Christianity as a power structure but divorce it from kings. Thus, from the 17th century onward, an entirely new system of racialization was devised and expanded including things like race science, anthropology, cherrypicking from religious and philosophical traditions, eventually incorporating Drawinian theory, and focused entirely on making the imperial project manageable.

In the US you see this pretty damningly with regards to the native population. They were a different race, they were not Christians, they needed to be mass murdered, their lands needed to be blighted and destroyed, their ways of life (plants, animals, and water) needed to be made extinct and poisoned beyond repair. To do this, the US needed to field a military into the frontier. That's the source of every town named "Fort Something". Those forts were created to exterminate and oppress native Americans. Those towns never stopped being that. It's just that they were victorious in their extermination campaigns. The laws are still on the books. The police force is still descended from the institutions of genocide. The roads, ports, prisons, residential neighborhoods, waterways, industrial zones, and agricultural zones around those towns are the living embodiment of the displacement efforts that trace themselves back to the frontier forts and their genocidal program, founded on racism.

And even The Guardian, shite rag that it is, is able to write about it.