Battle of Lyndanisse in the context of "Duchy of Estonia (1219–1346)"

The Northern Crusades or Baltic Crusades were military campaigns undertaken by Catholic Christian military orders and kingdoms in an effort to Christianize the pagan Baltic, Finnic, and West Slavic peoples around the southern and eastern shores of the Baltic Sea. In some cases, such as with the Wendish Crusade, the campaign was partly motivated to control the rich resources found in the lands.

The most notable of these campaigns were the Livonian and Prussian Crusades. Some of these wars were explicitly regarded, during the Middle Ages, as crusades; for example, the military venture against the Estonians—and the "other pagans in those parts"—authorized by Pope Alexander III's 1171 crusade bull, Non parum animus noster. However, others—such as the (possibly mythical) 12th-century First Swedish Crusade and several subsequent incursions, undertaken by Scandinavian Christians against the then-pagan Finns—were dubbed "crusades" only in the 19th century, by romantic nationalist historians.

The Dannebrog (Danish: Dannebrog, pronounced [ˈtænəˌpʁoˀ]) is the flag of Denmark. The flag is red with a white Nordic cross, which means that the cross extends to the edges of the flag and that the vertical part of the cross is shifted to the hoist side.

A banner with a white-on-red cross is attested as having been used by the kings of Denmark since the 14th century. An origin legend with considerable impact on Danish national historiography connects the introduction of the flag to the Battle of Lindanise of 1219.

Tallinn is the capital and most populous city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finland of the Baltic Sea, it has a population of 456,518 as of 2025 and administratively lies in Harju County. Tallinn is the main governmental, financial, industrial, and cultural centre of Estonia. It is located 187 km (116 mi) northwest of the country's second largest city, Tartu, however, only 80 km (50 mi) south of Helsinki, Finland; it is also 320 km (200 mi) west of Saint Petersburg, Russia, 300 km (190 mi) north of Riga, Latvia, and 380 km (240 mi) east of Stockholm, Sweden. From the 13th century until the first half of the 20th century, Tallinn was known in most of the world by variants of its other historical name Reval.

Tallinn received Lübeck city rights in 1248; however, the earliest evidence of human settlement in the area dates back nearly 5,000 years. The medieval indigenous population of what is now Tallinn and north Estonia was one of the last "pagan" civilisations in Europe to adopt Christianity following the Papal-sanctioned Northern Crusades in the 13th century. The first recorded claim over the place was laid by Denmark after a successful raid in 1219 led by King Valdemar II, followed by a period of alternating Scandinavian and Teutonic rulers. Due to the strategic location by the sea, its port became a significant trade hub, especially in the 14–16th centuries, when Tallinn grew in importance as the northernmost member city of the Hanseatic League. Tallinn Old Town is one of the best-preserved medieval cities in Europe and is listed as a UNESCO World Heritage Site.

Anders Sunesen (also Andreas, Suneson, Sunesøn, Latin: Andreas Sunonis) (c. 1167 – 1228) was a Danish archbishop of Lund, Scania, from 21 March 1201, at the death of Absalon, to his own death in 1228.

He is the author of the Latin translation of the Scanian Law and was throughout his life engaged in integrating a Christian worldview into the old legislature. He managed to introduce tithe (taxation benefiting the church) despite the resistance this measure had met from the population of Scania during Absalon's time, but his efforts to convince the priests of his day about the merits of celibacy was based mostly on his own example and relied on oratory rather than legal maneuvering. To educate the priests and to forward his ideas, especially about the integration between church and state, he wrote a didactic poem, Hexaëmon, consisting of 8,040 verses of Latin hexameter.

Tallinn is the capital and most populous city of Estonia. Situated on a bay in north Estonia, on the shore of the Gulf of Finland of the Baltic Sea, it has a population of 456,518 as of 2025 and administratively lies in Harju County. Tallinn is the main governmental, financial, industrial, and cultural centre of Estonia. It is located 187 km (116 mi) northwest of the country's second largest city, Tartu, however, only 80 km (50 mi) south of Helsinki, Finland; it is also 320 km (200 mi) west of Saint Petersburg, Russia, 300 km (190 mi) north of Riga, Latvia, and 380 km (240 mi) east of Stockholm, Sweden. From the 13th century until the first half of the 20th century, Tallinn was known in most of the world by variants of its other historical name Reval.

Tallinn received Lübeck city rights in 1248; however, the earliest evidence of human settlement in the area dates back nearly 5,000 years. The medieval indigenous population of what is now Tallinn and north Estonia was one of the last "pagan" civilisations in Europe to adopt Christianity following the Papal-sanctioned Northern Crusades in the 13th century. The first recorded claim over the place was laid by Denmark after a successful raid in 1219 led by king Valdemar II, followed by a period of alternating Scandinavian and Teutonic rulers. Due to the strategic location by the sea, its port became a significant trade hub, especially in the 14–16th centuries, when Tallinn grew in importance as the northernmost member city of the Hanseatic League. Tallinn Old Town is one of the best-preserved medieval cities in Europe and is listed as a UNESCO World Heritage Site.

The Duchy of Estonia (Estonian: Eestimaa hertsogkond, Danish: Hertugdømmet Estland, Latin: Ducatus Estoniae), also known as Danish Estonia, was a direct dominion (Latin: dominium directum) of the King of Denmark from 1219 until 1346 when it was sold to the Teutonic Order and became part of the Ordensstaat.

Denmark rose as a great military and mercantile power in the 12th century. It had an interest in ending the frequent Estonian attacks that threatened its Baltic trade. Danish fleets attacked Estonia in 1170, 1194, and 1197. In 1206, King Valdemar II and archbishop Andreas Sunonis led a raid on Ösel island (Saaremaa). The Kings of Denmark claimed Estonia, and this was recognised by Pope Honorius III. In 1219, the fleet of Valdemar II landed in the harbor of Lindanise (Tallinn) and defeated the local Estonians in the Battle of Lindanise. This brought northern Estonia under Danish rule until the Estonian uprising in 1343, after which the territories were taken over by the Teutonic Order. They were sold by Denmark in 1346.