There appear to have been some mixed-race people among the people often called "Vikings" (i.e., the people from among whom the pirates known as "Vikings" usually came). Specifically, a mitochondrial gene (C1e) was discovered in 4 families in Iceland; this belongs to a family of mitochondrial genes (C1) normally only present in Indigenous American and East Asian populations. These 4 families had common ancestors in the early 18th century, and due to the isolation of Iceland at that time, the most likely explanation appears to be that Vikings brought an American woman back to Iceland. (Note that mitochondrial DNA is inherited from the mother only, unlike nuclear DNA which is inherited from both mother and father.)

It isn't certain that these mitochondrial genes were present in the Icelandic population during the Viking age, but it is likely. Whether any children or grandchildren of this probably American ancestor became pirates/raiders (i.e., "Vikings" in the strict sense) is unknown.

Reference:

Jean Manco, Ancestral journeys: The peopling of Europe from the first venturers to the Vikings, Thames & Hudson, 2016.

I'll copy and paste my answer from the AC: Valhalla AMA, where it was asked whether there were any BIPOC Vikings.

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Probably. The Vikings are known to have raided in North Africa and taken slaves from there. Here is an Irish account from the 11th century about a Viking raid of Morocco in the 860s:

The king of the Mauritanians escaped from the camp and fled in the night after his hand had been cut off. When the morning came, the Norwegians seized their weapons and readied themselves firmly and bravely for the battle. The Mauritanians, however, when they noticed that their king had departed, fled after they had been terribly slain. Thereupon the Norwegians swept across the country, and they devastated and burned the whole land. Then they brought a great host of them captive with them to Ireland, i.e. those are the black men. For Mauri is the same as nigri; 'Mauritania' is the same as nigritudo. Hardly one in three of the Norwegians escaped, between those who were slain, and those who drowned in the Gaditanian Straits. Now those black men remained in Ireland for a long time.

As Caitlin Green discusses in her analysis of this passage, the 11th century annal is a fragmentary source compiled from bits of other Irish annals, so it is not the most straightforward source to use. However, the general idea that the Vikings raided North Africa in the mid-9th century is corroborated by Islamic sources. The Spanish writer Al-Bakrī wrote, for example,

Majūs [Vikings]—God curse them—landed at Nakūr [Nekor, Morocco], in the year 244 (858–859). They took the city, plundered it, and made its inhabitants slaves, except those who saved themselves by flight. Among their prisoners were Ama al-Raḥmān and Khanūla, daughters of Wakif ibn-Mu'tasim ibn-Ṣāliḥ. [The emir] Muḥammed ransomed them. The Majūs stayed eight days in Nakūr.

A few skeletons identified as belonging to women from sub-Saharan Africa found in England that date between the 9th and early 11th centuries have also been suggested to have been the descendants of slaves, or slaves themselves, who came to England via the Vikings. Two were found in East Anglia which was a particular hub of Scandinavian settlement.

Now, did people captured as slaves become "Vikings"? We don't have any evidence that they necessarily joined the ranks of aristocratic warriors we typically think of as "Vikings". However, these aristocratic men often had children with their slaves, as the high proportion of Irish descent in Iceland through the maternal line as identified in DNA studies shows. So there's no reason to suspect that slaves from North Africa wouldn't have been integrated into the Viking social structures the same ways that slaves from Europe were. Slaves were an integral part of Viking economies and while some were sold off to other places, others were kept to help in Viking households throughout Scandinavia and the diaspora. We know from Al-Bakrī's account that aristocratic women captured were sometimes ransomed back, but the commoner women captured in slave raids would not have been so lucky.

So it's quite likely that North African slaves, when brought back to Viking regions such as in the example given in the Irish annal, would have been employed in Viking households caring for animals, producing household goods (we know women slaves were particularly involved in dairying), and, sadly, serving the sexual whims of their captors. We'll never know for certain whether one of the children of a North African slave woman and a Viking man took up arms himself as a "Viking", defined in the narrow sense of the raider, but they certainly would have been members of "Viking" society.