Nathan Bernard was born December 9, 1951 in Chicago. His parents were David L. and LaVeta I. Habegger. He was the second child in a family of five children. The family was living in the neighborhood of the Mennonite Biblical Seminary. His father was completing a master of theology degree. In 1952 the family moved to Carlock, a little town in central Illinois, where David had become pastor of the Carlock Mennonite Church. The family lived there until 1954. The parsonage had a large garden where the family kept chickens and a sandbox where Nathan played. In 1955 the family returned to Chicago where David worked as I-W coordinator for Mennonite Central Committee (alternative to military service). In 1956 the family moved to Allentown, Pennsylvania, where David pastored First Mennonite Church. The family lived there until 1962. Nathan attended Franklin Elementary School. During his free time, he enjoyed competitive swimming and playing board games like Monopoly and Risk with his brother Chris and sister Rachel, and friends in the neighborhood.
In 1962 the family moved again to Upland California, where David became pastor of First Mennonite Church. Nathan completed elementary and junior high school and the first two years at Upland High School. Both Nathan and his brother Chris had local newspaper routes and by bicycle delivered to subscribers living in the neighborhood, a way to earn pocket money. During these years Nathan played Little League and Pony League baseball, mostly third base.
In 1967, the family moved again to Elkhart, Indiana, where David became pastor of the Hively Avenue Mennonite Church. The adolescent Nathan became engaged in political movements. Notably, in the winter of 1967-68 he participated in a march with Dr. Martin Luther King, Jr., which was captured in a photo that appeared in Time magazine. In May 1968, Bobby Kennedy was a candidate for the U.S. presidency and Nathan was photographed at Kennedy’s Indiana campaign rally, which appeared on the cover of the May 20, 1968 Newsweek magazine. In August 1968, Nathan went to Chicago where the Democrat Party was holding their convention to protest the war in Vietnam.
Nathan was competitive at games and also ambitious intellectually. He always knew that he wanted to attend college and maybe pursue a doctorate. He participated regularly in math competitions and was selected to participate in an elite math camp for high school students at St. Olaf College in Minnesota. Nathan received his diploma from Elkhart High School in 1969 and began studying at Bluffton College in Ohio. He participated in a variety of activities: cross country, choir and a traveling music group.
In 1971 Nathan decided to take a gap year and travel, partially because he didn’t want to register for military service (which was obligatory) and risk being drafted for the war in Vietnam. He headed first for Switzerland, the homeland of the American Habeggers, following contacts given to him by his father David. That’s how he arrived in Tramelan and became involved in activities of the Mennonite community of Sonnenberg. At a Mennonite ski camp, he met Anne-Catherine Bischoff, his future wife.
After meeting Anne-Catherine, Nathan continued traveling through the Middle East, Iran, Afghanistan (partly on horseback), Pakistan, India. He returned to Europe via a special flight from an NGO that had delivered food to India. Nathan received his college diploma in 1973 and was accepted into a master’s degree program in mathematics at Indiana University. There he lived with his brother Chris. He returned to Europe to reconnect with Anne-Catherine and to convince her to follow him to the United States. They were married on June 15, 1974 in Elkhart, Indiana. Nathan and Anne-Catherine stayed in the United States while he was completing his master’s degree. They then moved to Geneva, Switzerland, as Nathan had received a Fulbright Fellowship to begin his doctorate. He completed his doctorate in mathematics, specializing in topology, in 1981. During this period Nathan and Anne-Catherine had their first two children: Benjamin (1977) and Jeremy (1979).
Nathan’s career teaching mathematics at the university level involved professional opportunities requiring many moves. In 1983 the family left Geneva for Connecticut in the United States where Nathan had obtained a three-year assistant professor position at the prestigious Yale University. In 1984 during a brief stay in Bienne, Switzerland, a third son, Samuel, was born to the family. Between 1985 and 1987 the family was located in California where Nathan taught at the University of California–San Diego. They returned to Switzerland for the birth of their fourth child and first daughter Saralina at the end of 1987, where they stayed until mid-1988. The family returned to the United States where Nathan had accepted the position of mathematics professor at the University of Georgia in Athens. A fifth child joined the family, Rachelle (1989). Thinking that the move to Athens was permanent, they bought a house. However, after all the years of moving about, there was one more change, this time to France, where Nathan obtained a position at the University of Nantes. Their last child, Timothée, was born there in 1991. The family resided for ten years in Saint-Philbert de Grand-Lieu. During these years, Nathan devoted his time to research in topology (on the theory of knots), advising doctoral students, presenting at many conferences in many different countries. He traveled as far as New Zealand with his third son to participate in a conference organized by Vaughan Jones, a famous colleague and old doctoral comrade in Geneva who received the Fields Medal in Kyoto in 1990. In his free time he enjoyed playing tennis, participating in numerous tournaments, and continued to enjoy board games (chess, Risk, etc.) and music (choral, guitar). For his children he organized camping trips, trips to the beach, tennis in summer and skiing in winter during vacations in Switzerland with his in-laws.
In 2000, after more than twenty-five years of a relationship marked by numerous ups and downs linked to an as yet undiagnosed psychological disorder, Anne-Catherine and Nathan separated. They settled into a new family dynamic. The three youngest children of Anne-Catherine and Nathan moved to Tramelan in Switzerland, where Anne-Catherine’s family lived, while the three oldest stayed in France. Nathan was particularly responsible for Samuel, age 16 at the time, while the oldest two were already independent. The three youngest children spent almost all of their school vacations with their father. During this period Nathan met Fabienne Onillon and her two daughters Claire and Lison with whom he lived in Nantes.
In 2004, after a series of incidents judged disturbing by his children, Nathan was committed to a psychiatric hospital. These episodes had reoccurred over the years and likely caused the break-up with his wife and contributed to tensions within the family. It is clear that Nathan passed through phases during which he would be full of energy and undertake big projects, would sleep little, be hyperactive in sports, adopt sometimes risky behaviors outside of social norms, engage in questionable financial investments, and for those around him he would become extremely difficult to live with. At the other extreme, during other periods Nathan would close in on himself with a slow and inactive routine, focusing on one thing for a whole day (a game like Backgammon, a mathematical calculation, etc.). While these extreme behavioral swings did not lead to a diagnosis for a long time, finally he was diagnosed with bipolar disorder.
After a short hospital stay, Nathan returned to his activities and continued his relationship with Fabienne. They moved to Carheil where Nathan had bought a house. The relationship with Fabienne ended abruptly in 2007, when Nathan was going through a new, irrational manic phase while visiting his son Benjamin who had recently become father to twins Margot and Alex. Rather than returning to Nantes he traveled to Switzerland to reconnect with Nicole Moser, an old friend who had been nanny to his oldest children while they were living in Geneva, and to begin a four-year relationship marked by crazy adventures but also deep depression following the death of his mother LaVeta in 2008. In 2011, Nathan and Nicole also separated after a new manic phase. These recurring highs and lows also affected more and more his close relationships and were the cause of the gradual estrangement of his children who were now adults living far from Nantes, and several friends. His last manic episode unhappily occurred at his workplace, the University of Nantes, prompting the university to place Nathan on a prolonged leave of absence lasting up to retirement. Nathan was again hospitalized at a psychiatric center. Upon release he was relatively broken and took refuge with Jessica Joguet whom he met before his hospitalization, and with whom he lived the last five years of his life as a recluse.
He only kept in contact with his children and his brothers and sisters, by telephone or when possible visits in Nantes. Every year he was invited to join his children at Christmas (which he spent with them in 2015 in Bilbao, in 2016 in Annecy and in 2018 in Switzerland). Thanks to these reunions he was able to meet his grandchildren born in recent years: Naira (2014), Naima (2014), Meryl (2015), Léon (2016), Tomàs (2016), Arthur (2017), Alba (2018) et Elai (2018). During this last period of his life, he loved playing and following Go games online. As Nathan’s health continued to decline, he suffered particularly from osteoarthritis and more and more refused to go out and move. He died suddenly on October 10, 2020 as the result of a ruptured aneurysm.