Hallo from Germany by Ivo Dubiel there are about 630 telefon numbers with "Dubiel" in Germany. Later comes Dubielcyk and Dubielski. The web sides with "Dubiel" are frecuently Polish. So I have to suppose that Dubiel is a name of Polish origin. Someone in Poland many years ago suggested the same to me.
To most Germans Dubiel sounds French but there are no Dubiel in Paris as the telephonebook shows. I have been told by my parents that Dubiel is a French and thar we are descend from prostestant Hugenots who had to flee France because of their religion. Actually there has been Hugenot imigration in Silesa and we have an old family picture of someone looking like Hamlet with a great iron cross.
But the origins of that tale are probably sicological: My family belonged to the flour of that town Hirschberg in Silesia. My grandfather had the titel of "Geheimer Gerichtsrat". After World War I the population of Silesia voted in favour of Germany but despite of the election the Polish army attacked. So the Germans formed an ilegeal army and fought back. Because of this hatred among Germans in Silesia against Poland, it was impossible that my family name was Polish. And to those not knowing France it sounded French. Now Silesia,the home of my family, is Polish anyway because of World War II. But if in 10 years Poland forms part of the European union, borders within Europe have lost their importance.