This section is not concerned with sculpture in bronze, but rather with the many artistic applications of the metal in connection with architecture, or with objects for ecclesiastical and domestic use. Why bronze was preferred in Italy, iron in Spain and Germany and brass in the Low Countries cannot be satisfactorily determined; national temperamente is impressed on the choice of metals and also on the methods of working them. Centres of artistic energy shift from one place to another owing to wars, conquests or migrations.