In the 1200s the German crusaders converted Estonia into a Christianity by force and took control over South Estonia. In 1219 Denmark conquered Northern Estonia. About a century later, in 1346 Denmark sold its territory to Germany. By the 1500s German nobles owned much of Estonia's land. After the Livonian War (1558-1583) the northern part of Estonia went under Swedish control, the southern part belonged to Poland and the islands to Denmark. Only in1629 the whole mainland Estonia became subject to Sweden. Under Swedish rule the University of Tartu was founded in 1632 and also the oldest school working on the same premises was founded in Tallinn (GAG).After the Northern War (1700-1721) Estonia became a province of Russia. During that period the gentry of Baltic-German origin prevailed in Estonia. They kept estates in Estonia until 1919. Under Russian rule the Palace of Kadriorg was built and the park was laid out.
While Denmark took the northern part of Estonia, the knights occupied the southern portion. In 1346 the Danes sold their territory to the order, and Estonia remained under the rule of the knights and the Hanseatic merchants until the order's dissolution in 1561. Northern Estonia was then passed to Sweden, the rest was briefly held by Poland but was transferred to the Swedes by the Treaty of Altmark in1629. It ended the first Polish-Swedish war. German nobles--the Baltic barons--kept their sway over the Estonian peasantry until the eve of the 1917 Russian Revolution. Industrialization proceeded during the 19th century. The republic became heavily interlaced with railroads, and the port of Tallinn grew in importance. Russification took place and it caused rebellion and considerable emigration mostly to the United States and Canada. The Twentieth Century