Short answers, pulled from the story.
Västergötland is one of the 25 traditional non-administrative provinces of Sweden, situated in the southwest of the country. It is bordered by Bohuslän, Dalsland, Värmland, Närke, Östergötland, Småland, and Halland, and is flanked by Sweden's two largest lakes, Vänern and Vättern.
Västergötland is considered the heartland of the ancient Geat kingdom and the bridgehead through which Christianity entered Sweden. King Olof Skötkonung is held to have been baptized at Husaby near Lake Vänern around 1000, and excavations at Varnhem suggest its central parts were Christian as early as the 9th century.
When the provincial law Västgötalagen was written in the 13th century, Västergötland had 517 churches. The diocese's seat has been in the city of Skara since 1150.
Läckö Castle on the island of Kållandsö in Lake Vänern was begun in 1615. Jacob De la Gardie supervised the construction, and his son Magnus Gabriel de la Gardie completed it. A fortress had stood on the island since as early as 1298.
As of the 31st of December 2016, Västergötland had a population of 1,328,128 distributed across four counties. The largest share, 1,305,659, lived in the part of Västra Götaland County that falls within the province.
Karlsborg Fortress, situated in the town of Karlsborg in Västergötland, is described as the largest fortress in Europe. It was built as a testament to the 19th-century Central Defence Principle, a strategic doctrine that arose in direct response to Sweden's loss of Finland as a buffer state in 1809.