My family name, Rossell, isn't very common.
There is a town in Castelló that has my name, but I don't think my family came from that place.
I think my surname derive from Rosselló, a French region. In the Middle Ages there was a considerable immigration from the south of France to Catalunya.
My district in El Masnou, Ocata, was named after Leucate (coastal town of El Rosselló). The reason was in late XIX century a grupe of leucatins established there and gave to the area the name of their original town.
There are several forms of my name: Rosel, Rosell, Rossell.
My surname Rossell, have been identified as Sephardic (Jewish) name. It possibly comes from Roszel.
In Andorra you can visit The Forge Rossell. The Rossell and Areny families controlled the Andorran Siderurgy in the 18th and 19th century.
When I visited Scotland, someone said me my surname could derive from Russell. Who knows...