That's very interesting that Olson (Swedish Version) actually comes from Olafsson. According to my research and family stories My 2nd Great Grandfather from Bredared, Vastra Gotaland, Sweden was named "Olof Andreasson" - if you were to mash those names together it could be "Olafsson".
It is also Swedish, with the spelling of Olson rather than Olsen. It was originally Olafsson, but was altered when passing through Ellis Island. [noted -ed]
Usage: English
Pronounced: AWL-sən (English)