Henry M. Sayre was born in 1948 in Boulder, Colorado where he was also raised. Sayre grew up exploring the outdoors and developed an appreciation for art at an early age.

When he was fourteen, Sayre moved to New Hampshire to attend Phillips Exeter prep school, and in 1966 he began undergraduate studies at Stanford University, where he majored in English and was active in the anti-war movement. After graduating, Sayre moved on to the University of Washington to continue his education. Sayre wanted to explore landscape artwork as an idea and, as such, he took many art history courses, though his Ph.D. was in American Literature, completed in 1976.

After completing his doctorate, Sayre served as a visiting professor at Wake Forest University, where he worked until 1979. During this time his first son, Robert, was diagnosed with cancer at the age of two. Sayre quit his job to stay home and care for his son while his wife continued to work. This time spent at home allowed him to write art pieces for various publications, and led to a contact from Oregon State University in 1981. OSU's art department had suddenly found itself without an Introduction to Art instructor, and the university hired Sayre as a visiting professor to fill that spot. So began Sayre's career both at OSU and as an art historian.

In the mid-1980s, the Prentice-Hall publishing house approached Sayre with a request that he write a textbook on art interpretation and description. Sayre completed the book, Writing About Art, in 1989. Prentice-Hall then approached Sayre to write an art appreciation text, which he completed in 1994. This book, A World of Art, broke new ground in its approach, particularly through its focus on female artists, artists of color and lesser known figures from around the world. (Later editions of the text also incorporated electronic additions created by students.) Three years after the book's publication, components of its content were used in a ten-part television series, "A World of Art: Works in Progress," that aired nationally on PBS. The textbook, A World of Art, is presently in its seventh edition, with an entirely digital eighth edition soon to be released.

In 1999 Sayre was honored as Distinguished Professor of Art History at OSU, and as his profile rose his courses steadily grew in size. With his classrooms becoming more crowded, Sayre found himself missing the connections that he had been able to make with his students before he was teaching to a few hundred students at a time. Partly because of this, in 2001 Sayre chose to move to Bend to help start the OSU-Cascades campus. Now primarily an administrator, Sayre served as an academic provost and as chair of the curriculum committee, in addition to teaching much smaller classes.

Sayre also became involved in the Oregon Arts Commission after being appointed by Governor Ted Kulongoski in 2006. The commission was charged with awarding grants to artists in Oregon and Sayre served until 2011, when he and four other members resigned in protest after the committee's director was forced out.

Sayre is the author of nine books and throughout his time as an administrator he has continued to write. In 2005 he published a children's book, Cave Paintings to Picasso: The Inside Scoop on 50 Art Masterpieces, which won both an Oregon Book Award and the Eloise Jarvis McGraw Award for Children's Literature. He is also the author of a six volume work, The Humanities: Culture, Continuity, & Change (2007) as well as 2009's Discovering the Humanities.