He received a bachelor's degree from the University of Wisconsin School of Journalism in 1937.
His first professional work as a journalist was for the Pittsburgh Sun-Telegraph. He later wrote for the New York Herald Tribune.
His first play, Men to the Sea, was produced on Broadway in 1944. Between 1945 and 1947 he served as the music critic for Time magazine. In 1950 Kubly became an associate professor of speech at the University of Illinois, but he left that position to accept a Fulbright grant to Italy, where he spent 18 months in 1950–1951.
He taught creative writing at San Francisco State College in the 1960s. From 1969 to 1984, he was an English professor and writer-in-residence at the University of Wisconsin–Parkside.
Fellow Wisconsin Academy of Sciences, Arts and Letters (Distinguished Contribution, to Literature award 1982). Member Edward MacDowell Association, Authors League American, Dramatists Guild American, Wisconsin Academy of Sciences, Arts and Letters, Pi Epsilon Delta, Theta Chi.
On October 28, 1989 he married Emily Florence Hill, and they adopted a child, Alexander.