Original sentence: After the short vassalage to Poland, the dynasty entered Henry the Lion's Duchy of Saxony in 1164 and the Holy Roman Empire in 1181 except for a Danish period from the late 1180s to 1227.As Pomerania's neighbors, especially the Margraviate of Brandenburg, sought to take over the rule in Pomerania from the Griffins, the dynasty was in constant need of allies, leading to intermarriage with other noble houses, especially those of neighboring Denmark, Rügen, Mecklenburg, Brandenburg and Poland.The House of Pomerania,   (, ), also known as House of Greifen  or House of Griffins , was a dynasty of dukes that ruled Pomerania from the 12th century until 1637
Edited sentence: As Pomerania's neighbors, especially the Margraviate of Brandenburg, sought to take over the rule in Pomerania, the dynasty was in constant need of allies, leading to intermarriage with other noble houses, especially those of neighboring Denmark, Rügen, Mecklenburg, Brandenburg and Poland.Kazimierz IV Słupski, an adopted grandson of Kazimierz Wielki was a serious contender for Polish throne.The House of Pomerania, (, ), also known as House of Greifen or House of Griffins , was a dynasty of dukes that ruled Pomerania from the 12th century until 1637.The noble house was part of Polish realm till 1164 when it entered Henry the Lion's Duchy of Saxony, and was subjected the rule Holy Roman Empire in 1181, except for a Danish period from the late 1180s to 1227.Throughout their exstance the House of Pomerania, mainted close contacts with Poland