I descend from Ollar/Olar/Olariu from Hungary/Arad, Romania.
I think the name was originally Olariu (from a 1910 census - my great-grandfather Peter Olariu). The Ellis Island record on my Grandfather Florian says he is from Revetis, Hungary. He went back and married my grandmother Esther (Lajos) Ollar and brought her back. They eventually settled in Detroit, Michigan and he worked for Ford.
I haven't been able to trace back into Hungary, Romania.