Last name Ружен (Ружен 
, Rooijen 
) , across the world, is quite a rare cognomen. The cognomen Ружен is habitual in Netherlands, where it is quite a common surname, Belgium, where it is quite a rare surname, and Albania, where it is a rare surname. Not in comparison with a country's population, this name is the most popular in Western Europe, particularly Netherlands, Belgium, and Germany.