Lothar Baumgarten was born on Oct. 5, 1944, in Rheinsberg, Germany. His father Kurt, was an anthropologist, and his mother, Johanna, was an executive secretary at a bank.

He became interested in photography as a child.

“When I was 5,” he told Mousse Magazine in 2016, “I found that I couldn’t express myself clearly enough verbally to my father. I said to him, ‘I’d like to give you a picture from what I see.’ ” So his father gave him an Agfa box camera.

He graduated from the State Academy of Fine Arts Karlsruhe in 1968, and from 1969 to 1971 he studied at the Academy of Arts in Düsseldorf, where his teachers included Joseph Beuys.

Mr. Baumgarten began making photographic studies of displays at ethnography museums throughout Europe. Then came his stay in the Amazon, which he drew upon for several exhibitions in the 1980s, including one for the 1984 Venice Biennale, in which he embedded the topography of the Amazon River system into the floor of the German Pavilion.

In the late 1960s or early ’70s, he had a serendipitous encounter that ultimately helped bring him to attention in the United States as well. Ms. Goodman and a colleague were participating in an art fair in Düsseldorf when the colleague became ill, leaving Ms. Goodman, who was then early in her career as a gallerist, with 40 pictures to hang. The colleague called a local gallery and asked the owner whether someone was available to help.

“She sent over a young man, and he did a great job of hanging the work,” Ms. Goodman said. Only when he mentioned that he had a film showing nearby did she realize that he was an artist, not just a gallery assistant. It was, of course, Mr. Baumgarten, and she was soon presenting him in the United States.

His many exhibitions at the gallery included an installation in 1987 that focused on a hunting trip he had gone on while living with the Yanomami.