Rundgren

Swedish surname with somewhat unclear etymology. The first element is possibly taken from a place named with either of the elements rund and/or run. Rund coincides with the Swedish word for "round", but it is not clear if the element used in this name is derived from that word. Run could be derived from Old Swedish *røn "stony ground", from Old Swedish rudhme/rodhme "rust, something red", from dialectal (sörmländska) runn "rowan", or from dialectal (småländska) runne "bush". The second element is gren "branch".

The name can be found as Rungren in some genealogy records, but that spelling is obsolete in Sweden today.