Strait of Baltiysk
The Strait of Baltiysk (Russian: Балтийский пролив, Polish: Cieśnina Piławska, German: Pillauer Tief) is a strait enabling passage from the Baltic Sea into the freshwater Vistula Lagoon, located in Kaliningrad Oblast, Russia. The constructed strait separates the Sambian Peninsula and the Vistula Spit, and is at the northeastern side of the lagoon.
The strait is the shipping connection from the open sea to the important Russian ports of Baltiysk and Kaliningrad in the northeastern lagoon, as well as to the Polish ports of Elbląg, Braniewo, Tolkmicko, Frombork, Sztutowo, Krynica Morska, and Nowa Pasłęka in the southeastern lagoon.
In 1497 a storm surge dug a new gat, then called the Neues [Pillauer] Tief or Pillauer Seetief (New [Pillau] Deep, Pillau Sea Deep), through the Vistula Spit. In 1510 another storm surge widened and deepened that gat to navigability. It measured 550 metres (1,800 ft) in length and 360 metres (1,180 ft) in width. In 1626 King Gustavus Adolphus of Sweden landed with 37 ships next to the gat, at a spot already slightly fortified, transforming it into the Pillau Fortress, and holding it for ten years (till the Treaty of Stuhmsdorf), also in order to pressure his brother-in-law George William, Duke of Prussia and Elector of Brandenburg, to support him in the Polish–Swedish War and the Thirty Years' War. The Swedes extended the adjacent Pillau village and built its first place of worship, a Lutheran church. In 1638 the Duke moved his residence to the close-by ducal capital Königsberg in Prussia.
In the 1960s the gat was expanded and now it measures 400 metres (1,300 ft) in width and 12 metres (39 ft) in depth. Since the 1990s Russia periodically blocks navigation via the strait (both for Poland and Russian Kaliningrad Oblast). Since 2006, Poland has considered digging another canal across the Vistula Spit in order to circumvent this restriction.
While today the Kursenieki, also known as Kuršininkai are a nearly extinct Baltic ethnic group living along the Curonian Spit, in 1649 Kuršininkai settlement spanned from Memel (Klaipėda) to Danzig (Gdańsk). The Kuršininkai were eventually assimilated by the Germans, except along the Curonian Spit where some still live. The Kuršininkai were considered Latvians until after World War I when Latvia gained independence from the Russian Empire, a consideration based on linguistic arguments. This was the rationale for Latvian claims over the Curonian Spit, Memel, and other territories of East Prussia which would be later dropped.