Harold Jacobson was born in Detroit onJune 28,1929. He attended high school in Wyandotte, Michigan, and received a bachelor's degree in history from the University of Michigan. He married his Michigan schoolmate Merelyn Jean Lindbloom in 1951, a year after he started graduate school at Yale.

He was fundamentally an optimist about human behavior; he opened his path-breaking text, Networks of Interdependence, with the words, "This is an optimistic book, though I hope not an unrealistic one."

Thus did Jacobson begin a career-long association with many whose work was rooted in international law. This interest led to fruitful collaborations and innovative contributions to the international law literature.

His insatiable curiosity, open-mindedness, delight in discovery, and appreciation of people were grounded in a strong sense of his own community and identity.

An inspired and devoted teacher, Jacobson achieved excellence by fostering it.