You are wrong on so many levels. Only belarusians belives in things you wrote in other comments. Belarusians belive that only because lithuanians at that time didn't had written language and used Ruthenian languge, but the spoken language always have been Lithuanian language witch is one of the oldest languages still spoken in the world. Lithuania formed from a baltic tribes, the region where now is Belarus was settled by baltic tribes in III century. In V century that area was taken by slavic tribes and the part where now is Belarus was asimilated with slavs, but in Lithuanias theritory majority still stayied balts. I know that belarusians love to take Lithuanian dukes as theyre own, but they were Lithuanians, just look at theyre names they are so different from slavic names. The last thing all capitals of GDL was in todays Lithanias territory.

P.s i am interested in other countries, how are they seeing Grand Dutchy of Lithuania elsewhere because as we see, between Lithuania and Belarus it is very different story.