Born in Epsom, New Hampshire, Sanborn received an Artium Baccalaureus degree from Dartmouth College in 1867 and an Artium Magister degree from the same institution in 1870.

He was a high school teacher and principal in Milford, New Hampshire from 1867 to 1870.

[1] Sanborn was nominated by President Benjamin Harrison on February 10, 1892, to the United States Court of Appeals for the Eighth Circuit and the United States Circuit Courts for the Eighth Circuit, to a new joint seat authorized by 26 Stat.

He was confirmed by the United States Senate on March 17, 1892, and received his commission the same day.

His service terminated on May 10, 1928, due to his death in Saint Paul.