He was born in Joplin, Mo., in 1928. His father worked for Curtis Mathes Manufacturing, like his father before him. When World War II broke out, Long's father moved the family to Texas.
The Korean War changed his plans for grad school. He was on active duty in the Air Force for two years, based in Texas and Colorado. When he was assigned to French Morocco in 1951, his first wife, Jeannie Murchison Clout, was able to accompany him. When on leave, he would travel to Europe and visit museums.
His father told him he needed to get a job. Long went to work selling fans and air conditioners and eventually joined Curtis Mathes in 1954. Three years later, he refused a salary increase as inducement to stay with the company, moved to Houston and looked for space for his gallery. When he opened Meredith Long & Co. in 1957, Houston had a population of 872,000, two museums.
When Meredith Long and Cornelia Cullen married in 1967, they merged his and her children — three each from previous marriages — and a year later added their daughter Martha.