The original Swedish Bible Study Method was introduced into the Church of Sweden in the Swedish city of Västerås in the 1940's by David Berglund. It was popularised in many IFES student movements by Ada Lum. It is known in Sweden, and some other parts of the world, as the Västerås method.
From Wikipedia:
David Berglund introduced the method in the Church of Sweden in Västerås sometime in the 1940s (the so-called Västerås method with the "light, arrow and question mark" "ljus, pil och frågetecken"). Through Ebbe Arvidsson (an influential leader of the church) the method gained a wide impact not only in Västerås, but also in the whole Church of Sweden, and internationally.
(From the information available: it was initially used sometime between 1942 and 1950. Although from the context it was probably closer to 1942.)
On Blogspot, Sten Bertil Risberg (Retired) wrote about David Berglund and the Swedish Method 7 Nov. 2016:
During the years of high school in Härnösand came KGF, the Christian Asociation of Secondary Schools that became something of a second home for me as well as many others. The summer nights in Munkviken and the winter nights in Hampnäs were significantly influenced by this 'biblicism'. The reason for this was through the biblical studies using the so-called 'Västeråsmetoden'—that is, you read a series of biblical verses with a pencil in your hand. For what we did not understand, I would put a question mark, for a flash of light a candle was drawn, and for something that reached the heart or the conscience, an arrow.
It was an effective method, and I can still remember how the light came on when I suddenly realized the meaning of the Lutheran lesson "sim just a peccator", while reading the letter to the Romans, that is, "at the same time righteous and sinners". For young people it was a relief to hear that at the same time you could be both 'just' and 'sinful'.
The author of the Västerås method turned out to be David Berglund. A lasting bond was built with him. He became my friend and mentor.
The most important thing during these biblical studies was to come to the text of the Bible.
(Thanks to Sanja Wihk, exchange student from Sweden in Argentina, for the translation of these texts from the Swedish language.)