Fischer was born July 30, 1842 in DuPage County. In 1861 he enlisted in Company B. of the 33rd Illinois Volunteer Infantry and was mustered out in 1864. He later attended Oberlin College from which he graduated in 1874 after study in the classical course. He then studied medicine abroad. In 1874 he received a Master's degree from Wheaton College. The following year he graduated from the Ohio Medical College in Cincinnati. He returned to DuPage County and practiced medicine in Elmhurst. He served for 24 years as a trustee of Wheaton College.