sentences:  The name highlights the importance of fish farming for the city's economy in the Middle Ages, which is reflected in its coat of arms until this day.The city's origins can be traced back into the 9th and 10th century, when three Slavic settlements existed on Rybnik's present-day territory which eventually merged to form one town.In the course of the medieval eastward migration of German settlers ("Ostsiedlung"), Rybnik, as many other Polish settlements, was incorporated (granted city status and right) according to the so-called Magdeburg Law at some point before 1308 (the exact date remains unknown).