The subclade of G-FGC34846 is very interesting because it is found in Scandinavia, which is not where most people think of when they think of G. As far back as 700 years ago one of these men established several lineages in Västerbotten County.
However it makes sense that there could be G in Sweden because the neolithic package, along with some DNA was brought to Scandinavia by the First Farmers of Europe.
However, this particular subclade of G, by YFull samples, does not appear to have any Scandinavian diversity before 1100 BC. The next several subclades up the tree have no Scandinavian samples. So it is likely that FGC34846 was this first of this lineage to migrate to Sweden.
Going by YFull samples alone, northern Germany or Sweden seems like a possible origin for FGC34846. There are two different lineages which diverged 1100 BC and are now found in Sweden (G-Z30729 and YF03369), one in Austria and one American. If this theory is correct it could mean that the Austrian came with Germanic speaking migrants from further north.
The subclades above this are very widely distributed and we would need more samples than what is currently on YFull in order to be sure of where they were living.
An interesting parallel is that E-FGC11457 also first migrated to Scandinavia around the same time. They both also have presence in Poland from the same diversification point. This E lineage seems reliably from the Balkans while I do not think it is clear where Y3098 originated, given the high geographic diversity. What is clear is that Y3098 has no Balkan presence so likely didn't come from there.
This could be an example of different groups having come together to take part in the Tollense River Battle.
These posts are the opinion of Hunter Provyn, a haplogroup researcher in J-M241 and J-M102.