Sigfús Runólfsson was born in S. Múlasýsla in 1860. He took the name Frank R. Johnson in the west.
Spouse: Sigurbjörg Arngrímsdóttir b. 1867 in N. Múlasýsla.
Children: 1. Arnólfur b. 1887 2. Guðný María b. February 16, 1891 3. Sigfúsína Sigurbjörg b. 1896 4. Valdimar Eymundur b. 1898 5. Margrét Evangeline b. 1901 6. Alice b. 1903.
Sigfús came west in 1877 and travelled to Minnesota. He settled in Minneota and took an active part in shaping the community there. He served on the fire brigade, ran the Icelandic Co-op, and served on the town council from 1885 to 1892. He owned and operated the Minneota Clothing Store until 1892. Shortly afterwards, the entire family moved west to the Pacific Ocean and settled in Seattle. Sigurbjörg moved west to Minnesota with her siblings in 1879 and settled in Minneota.