Terra Mariana, eventually comprising present-day Latvia and Estonia, is established.

Terra Mariana was the formal name for Medieval Livonia or Old Livonia. It was formed in the aftermath of the Livonian Crusade, and its territories were composed of present-day Estonia and Latvia. It was established on 2 February 1207, as a principality of the Holy Roman Empire, and lost this status in 1215 when Pope Innocent III proclaimed it as directly subject to the Holy See.

Latvia, officially the Republic of Latvia, is a country in the Baltic region of northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to the southeast and shares a maritime border with Sweden to the west. Latvia covers an area of 64,589 km² (24,938 sq mi), with a population of 1.8 million. The country has a temperate seasonal climate. Its capital and largest city is Riga. Latvians, who are the titular nation and comprise 65.5% of the country's population, belong to the ethnolinguistic group of the Balts and speak Latvian. Russians are the most prominent minority in the country, at almost a quarter of the population; 37.7% of the population speak Russian as their native tongue.

Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Russia. The territory of Estonia consists of the mainland, the larger islands of Saaremaa and Hiiumaa, and over 2,300 other islands and islets on the east coast of the Baltic Sea. Its capital Tallinn and Tartu are the two largest urban areas. The Estonian language is the official language and the first language of the majority of its population of nearly 1.4 million. Estonia is one of the least populous members of the European Union and NATO.