Vincent Hartgen, the prolific painter and passionate art teacher who influenced a generation of artists and established the University of Maine art department, as well as its extensive art collection, died Wednesday in Bangor after a long illness. He was 88.

A visionary whose approach to education extended beyond the classroom and into the everyday life of residents in far-flung areas statewide, Hartgen not only was a progressive teacher but he also collected art with an impresario’s insatiability. Almost single-handedly, he was responsible for acquiring more than 5,000 works for the UM Museum of Art.

“More than 90 percent of what I see here was brought into the collection during Vincent’s watch,” Wally Mason, the museum’s current director, said Friday from the new UM gallery wing that opens Dec. 6 in downtown Bangor. “That speaks volumes in and of itself.

“It’s clear that Vincent’s legacy may be as an artist for some people, but it is also this wonderful art collection.”

Hartgen’s association with Maine began in New York City at an interview with UM President Arthur Hauck, who hired Hartgen to build an art department and museum at the Orono campus. With his wife, Frances, a meteorologist, he moved to Maine in 1946 and began a university career that spanned more than 30 years.

A fierce advocate of art education, Hartgen was a powerhouse in the classroom, sometimes standing on desks or banging on chairs to make his point. He once taught a class while lying on a table to emphasize the difficulties Michelangelo faced when painting the Sistine Chapel. For many years, he hosted summer art shows for students in the Japanese-style gardens in the back yard of his Orono home, a daffodil-yellow, architect-designed house. While some artists would refuse to teach introductory courses, Hartgen did not shy away from taking on entry-level art students. He was sometimes confrontational and cantankerous, but Hartgen was more widely known as affectionate, kind and generous.

Hartgen’s career was marked by many local distinctions including the first appointment to the John Homer Huddilston Professorship of Art Chair, the Black Bear Award, the Distinguished Professor Award and an honorary doctor of fine arts, all from UM. The Vincent A. Hartgen Award was established in 1999 to honor outstanding contributions to the advancement of the arts. It is distributed by the UM Patrons of the Arts, which Hartgen co-founded in 1963 to encourage and support undergraduate involvement in the arts.

Later in life, Hartgen admitted to coaxing, cajoling and haranguing any number of people to build the museum at UM. As head of the department, he made sure the artworks – among them pieces by Berenice Abbott, Jasper Johns, Diego Rivera, Giovanni Piranesi, Kathe Kollwitz, Andrew Wyeth and John Marin – were hung in offices around campus and that they traveled to schoolchildren statewide. If an administrator complained about Hartgen’s avant-garde taste in art, the tenacious educator might respond: “That’s why it’s here. You have to learn to like it.”

“I was trying to create a revolution here,” Hartgen said in a recent interview. “I wanted to teach and encourage people to enjoy art, particularly modern art.”

As a watercolorist, Hartgen drew inspiration from the natural beauty of Maine. His abstract paintings depicted the seascapes and landscapes he would drive many miles to observe. Accompanied by Frances, he would sketch in the field – Schoodic Point was one of his favorite spots – and then return to his Orono studio. There he created aquarelles, paintings done in transparent watercolors, that secured him a formidable place among Maine artists. He kept a sketch pad and pens by the door, he said, “in case anyone comes along and says ‘Do you want to go to the coast?'”

The New York City-based art critic Herbert J. Seligmann, responding to a show in the 1960s, wrote that Hartgen had “become the voice of all seasons in Maine, a great virtuoso of watercolor … he is in the direct line of the great American poets who have celebrated the native abundance of America.”

Born in 1914 in Reading, Pa., Hartgen showed a boyhood interest in nature and loved being in the woods. He studied architecture and fine arts at the University of Pennsylvania, where he also eventually earned a master’s degree in fine arts. During World War II, he served in the U.S. Army Camouflage Corps. He and Frances, who worked for the U.S. Weather Bureau, married in the 1940s.

In Maine, they raised twin boys, David, now a professor in North Carolina, and Stephen, a newspaper publisher in Idaho, while Hartgen stormed into action creating the department, shocking some art lovers by displaying nudes, challenging the formalities of the academy by forgoing suits and ties, and victoriously holding the chairmanship from 1946 to 1975. All the while, Hartgen was also a painter, who produced more than 3,500 major works during his lifetime.

“I’m not an artist by profession,” David Hartgen said, “but my impression is that he put Maine nature into motion for people. He wanted us to know that art was not just people sitting at a table or vases of flowers. He showed us that art is a part of life. My father saw Maine nature in its most spectacular and most subtle form and in its motion.”

Those same qualities attracted the Orono painter Michael Lewis to Hartgen as both an artist and as a friend. In 1966, Hartgen hired Lewis to teach art at UM. The two became more than colleagues over the years. They became friends and fellow artists. Hartgen’s last show, which closes today at Aucocisco, a gallery in Portland, was a two-man show with Lewis.

“The scope of what he did was enormous,” Lewis said. “He came to Maine when there was very little going on at the university and in the state. He wanted to introduce people to art and make it important in their lives. And he managed to accomplish this very ambitious goal.”

As an artist, Hartgen’s talents sprang from his sense of nature not as an object but as a force, said Lewis. He was technically accomplished with watercolors, one of the most difficult mediums in which to paint, and he was experimental up until his last paintings made just three weeks ago.

“When you look at the work, you can feel that energy,” Lewis said. “It’s also very honest. He’s not affecting anything. He’s giving you his full, furious, passionate, all-out response. Even when we were talking about this show we have together, he was deeply insightful, bluntly honest and sensitive in his responses.”

Castine-based sculptor Clark Fitz-Gerald praised Hartgen’s bold approach to trumpeting art to Maine and to establishing the respected UM collection. Like Fitz-Gerald, Hartgen believed art should be a presence in daily life as well as in specialized circumstances or venues.

“When you live a full life, you forget about the young man and his dynamics,” said Fitz-Gerald, who met Hartgen in the 1940s and shared the exhibition spotlight with him at the Farnsworth Art Museum in 1980. “He was aggressive, bright, gregarious and he was an artist. He could take any kind of work and display it better than anyone I know. But what he did at the art department at the University of Maine is everlasting.”

Hartgen is survived by his wife, two sons and three grandchildren.