"In 1193 Pope Celestine III called for a crusade against pagans in Northern Europe. The Northern Crusades from Northern Germany established the stronghold of Riga (in modern Latvia). With the help of the newly converted local tribes of Livs and Letts, the crusaders initiated raids into part of what is present-day Estonia in 1208. Estonian tribes fiercely resisted the attacks from Riga and occasionally themselves sacked territories controlled by the crusaders. In 1217 the German crusading order the Sword Brethren and their recently converted allies won a major battle in which the Estonian commander Lembitu was killed. The period of the several Northern Crusade battles in Estonia between 1208 and 1227 is also known as the period of the ancient Estonian fight for independence."
In Estonia, today's "History of" country, which looked like this before September 21, 1217: