The Swedes backed missions to secure Christian footholds in Estonia and in southern Finland, where in 1222 one Swedish king, John Sverkersson, was killed in a skirmish. Valdemar II, King of Denmark 1202-42, demonstrated the effectiveness of sea power by sending a fleet of deep-draught warships to seize the Estonian offshore island of Saaremaa in 1206, establishing a base from which he mounted an invasion of northern Estonia thirteen years later. On that occasion Valdemar came as a crusader and was accompanied by the Archbishop of Lund, two other bishops and their chaplains.
The campaign is steeped in legend. The formidable army that landed at Reval was thrown into confusion by an Estonian attack from the hill of Toompea. When the fighting became desperate the archbishop is said to have knelt in prayer, with hands raised in supplication: a red flag with a white cross upon it floated down from heaven, in token of God’s blessing on the Danish cause; and beneath the banner, Valdemar’s army went on to gain a historic victory. The emblem of Denmark today is still this Dannebrog, the oldest national flag in the world. And Estonia is the only republic with a capital named after the foreign invaders who made it a city; for the word Tallinn derives from the Estonian for ‘Danish Town’ (Tanni linn).
Soon Reval/Tallinn did indeed become in every sense a Danish town, founded little more than forty years after Copenhagen itself. A cathedral, eight churches, a nunnery and a Dominican abbey, all planted from Denmark, were grouped around the castle and royal treasury on Toompea hill, where the king’s lieutenant resided. Between Toompea and the quay-side everything essential to administer a distant dependency was concentrated – an arsenal, commercial warehouses, stables with horses kept ready for any expeditionary force from the homeland. It was, however, a curious form of ‘colonization’. After Valdemar completed a land settlement in 1242 the Danish kings never intervened in Estonian affairs. There was virtually no centralized control; nominal vassals enjoyed a rare independence on their territorial fiefs. The treasury remained in Danish hands but there were many months when the Sword Brothers were virtual masters of the growing city. Yet, despite these obstacles, during a 120-year period thirteen successive rulers of a country 1,300 kilometres west of Estonia could count on steady revenue from the tolls, tithes and taxes of their overseas colony.