Ostsiedlung

thumb|Stages of German eastern settlement in pink and three shades of green; the black line represents Holy Roman Empire borders in 1348 thumb|German language areas in 1910 in today's Poland, [[Kaliningrad Oblast (Russia), Lithuania, and Czech Republic before expulsion of Germans ]] '''' (, ) is the term for the early medieval and high medieval migration of Germanic peoples and Germanization of the areas populated by Slavic, Baltic and Uralic peoples; the most settled area is sometimes known today as . Germanization efforts included eastern parts of Francia, East Francia, and the Holy Roman Empire and beyond; and the consequences for settlement development and social structures in the areas of settlement. Other regions were also settled, though not as heavily. The Ostsiedlung encompassed multiple modern and historical regions, primarily Germany east of the Saale and Elbe rivers, the states of Lower Austria and Styria in Austria, Poland and the Czech Republic, but also in other parts of Central and Eastern Europe.

The majority of settlers settled individually at various stages. Many settlers were encouraged and invited by the local princes and regional lords, who sometimes even expelled previously settled people to make room for German settlers. Germanization also took place, particularly in Prussia, with estimated 80% of German-speaking East Prussians having Baltic or Slavic paternal origins in 1910.