John Joseph Byrne was born on July 11, 1932, in Paterson, New Jersey, to John J. Byrne and Winifred Mohr Byrne. As a teenager, he worked at his father’s insurance agency in Wildwood, New Jersey, according to a death notice on the website of Rand-Wilson Funeral Home in Hanover, New Hampshire.
He graduated from Rutgers University in New Jersey in 1954 and earned a graduate degree in mathematics from the University of Michigan. He began his career as an actuary at Lincoln National Life Insurance Co.
After Geico, Byrne led the Fireman’s Fund Insurance Co. until its acquisition in 1991 by Allianz AG Holding of Germany, now Allianz SE. (ALV) He retained control of the fund’s holding company, which he renamed Fund American Enterprises Inc. Today it is White Mountains Insurance Group.
Byrne served on the Board of Overseers of the Tuck School of Business at Dartmouth College in Hanover, which his three sons -- John, Mark and Patrick -- attended, according to the death notice.
He served on the board of Internet retailer Overstock.com Inc., the company his son Patrick led as CEO. The two clashed at one point over Patrick Byrne’s public campaign against short selling.
Besides his sons, Byrne’s survivors include his wife, Dorothy; seven grandchildren; and his brother, James Byrne, according to the funeral home.