Magnus was born in Alstakan, Gunnarskog parish, Värmland. He grew up in a poor family, and had to work hard. He found employment at Östlund & Almqvist in Arvika. He studied German and French and Greek during this time.
In 1895 he travelled to Kashgar, but being delayed, he studied Uyghur in Bukhara, and only arrived in Kashgar June the following year, 1897. In Xinjiang he worked at the Mission hospital.
On 26 June 1903 he died of typhoid, and was buried in Kashgar. He was 37 years old.