Schwarzbrot

Rye bread is a type of bread made with various proportions of flour from rye grain. It can be light or dark in color, depending on the type of flour used and the addition of coloring agents, and is typically denser than bread made from wheat flour. Compared to white bread, it is higher in fiber, darker in color, and stronger in flavor. The world's largest exporter of rye bread is Poland. Rye bread was considered a staple through the Middle Ages. Many different types of rye grain have come from north-central, western, and eastern European countries such as Iceland, Germany, Austria, Denmark, Sweden, Norway, Finland, Estonia, Latvia, Lithuania, Poland, Belarus, Ukraine, Russia, the Netherlands, Belgium, France, and the Czech Republic, and it is also a speciality in the canton of Valais in Switzerland. Around 500 AD, the Germanic tribe of Saxons settled in Britain and introduced rye, which was well-suited to its temperate climates.

Source: Wikipedia