X
Distribution map of mtDNA X

mtDNA X is a subclade of N and is estimated to have originated in the Near east about 30,000 years ago. Its subclade X1 is almost completely restricted to Near east, North Africa, and east Africa. But surprisingly there is a X1 sample from Can Sadurnı Spain dating to 7,475-7,305ybp from early Neolithic Cardiel culture but all other X subclades from Neloithic-iron age European samples are X2. X1 is broken down into two subclades X1a and X1b.
X2 is spread out in Europe, Near east, and North America. Wikpedia says that X2 seems to have undergone population expansion and dispersal about 21,000ybp during the last glacial maximum and that it is strongest in Meditreaen Europe, Near east, and Caucus and that is probably migrated to Europe during the last glacial maximum then spread in central and northern Europe when the glaciers retreated. X2 exists in Neolithic-Iron age European mtDNA samples at the same rate it does today so it at least came to Europe in the Neolithic age. Native American X2 is under subclades X2a and X2g. X2g has not been found in Europe or asia and X2a also exists in Israeli Druze. The X2 around the area of Asia all other Native American mtDNa and Y DNA lineages originated most likely came there through random inter marriage just 5,000 years ago and they could not find any evidence of Native American X2 there. It is estimated to have arrived in North America 15,000-20,000ybp while all other Native American mtDNA which all of their subclades are unique to them are estimated to be 18,000-22,000 years old so X2 may have come from another minor migration into North America. It would have gone through the Near east to Siberia to North America or Near to Europe to North America.
It has been used as evidence for the Solitarian Hypothesis which is that Paleoithic western European Solutrean culture made it eastern area of North America around 20,000 years ago. In North America X2 is mainly found in northeast and around the Great Lakes north America and then decreases the farther away so that can also be used as evidence. I think it went through Siberia with the main Native American mtDNA haplogroups but since it is restricted to one area maybe from another migration out of Siberia. The reason is the main mtDNA haplogroups of western Europeans at that time ancient DNA and studies have shown would have been U5, H1, and H3 who knows if X had even made it to Europe by that time and I would assume it would be harder to travel from Europe to north America than through asia. And who would keep migrating north father away from plants and animals for food it has been shown it was possible but I doubt Solutrean people would even want to. It makes more sense to me Mongliods in asia randomly into married with Caucasians from the Near east and for somereason only a few who had X2 then that maternal line made to North America 15,000-20,000ybp.
I and W
I could not find that much info on these mtDNA haplogroups. They exist in Europe, Near east, and south asia just like most Caucasian mtDNA haplogroups. Wikpedia says W is estimated to be about 23,900 years old and originating in the Near east it is a subclade of N2 and that there is a related unnamed N* subclade in Australian aboriginals. Which is surprising since Austrlien Aboriginals are apart of the Oceania Mongoliod family(
globe13) not Caucasian. They most likely left the middle east around 80,000 years ago while Caucasians ancestors stayed. mtDNA I is estimated according to Wikpedia to be about 20,857 years old and originating in the Near east or somewhere else in Europe and Asia. I couldn't find any info on when it should have arrived in Europe. They pop up in Neolithic European mtDNA samples at the same rare rate they are at today so they arrived into Europe at least with the spread of farming out of the Near east mainly 9,000-6,000ybp.