My g-grandfather owned 2 tracts of land in DeSoto Parish in Louisiana. He died in the Civil War. Shortly thereafter, his wife and children moved to Texas. I want to know what happened to the land he owned. Was it sold? Deeded to family? Abandoned and sold for taxes? I have the record on Ancestry where he purchased the land from the US General Land Office in 1860. How can I find what happened to this land?

It would be most likely sold. You would have to go to the parish clerk or court there in Louisiana and look up the deed from his family to somebody else. The record won't be with the GLO because they don't keep tract of land after they sell it; it's the local government's job.