The origin of the name "Polanie" itself derives from the early Slavic word "pole" (field).
In some languages, such as Hungarian, Lithuanian, Persian and Turkish, the exonym for Poland is Lechites (Lechici), which derives from the name of a semi-legendary ruler of Polans, Lech I.
The significance of the event was documented by Gallus Anonymus in his 1118 chronicle.
In 1138, Poland fragmented into several smaller duchies when Bolesław divided his lands among his sons.
The most famous archaeological find from the prehistory and protohistory of Poland is the Biskupin fortified settlement (now reconstructed as an open-air museum), dating from the Lusatian culture of the early Iron Age, around 700 BC.
This union formed the Polish–Lithuanian Commonwealth, one of the largest (about 1 million km which adopted Europe's first written national constitution, the Constitution of .These groups are identified as Celtic, Sarmatian, Slavic, Baltic, and Germanic tribes.Also, recent archeological findings in the Kujawy region, confirmed the presence of the Roman Legions on the territory of Poland.Poland began to form into a recognizable unitary and territorial entity around the middle of the 10th century under the Piast dynasty.Poland's first historically documented ruler, Mieszko I, accepted Christianity with the Baptism of Poland in 966, as the new official religion of his subjects.
These were most likely expeditionary missions sent out to protect the amber trade.