Born in Vienna, Gregor moved with his family to the United States in 1939 to escape World War II. He earned a BS from the Newark College of Engineering and worked first as an engineer, then as an editor, including as a senior editor for the Macmillan Company, before founding the department of Creative Writing and Publishing Studies at Hofstra University. At Hofstra, Gregor was poet-in-residence from 1986 until his retirement in 1995. Gregor’s poems were published in Poetry in 1947, and he received the First Appearance Prize. He is the author of 11 books of poetry, among them Octavian Shooting Targets (1954), Basic Movements (1966), Figure in the Door (1968), The River Serpent and Other Poems (1995), and That Other Side of Things (2001).

Gregor’s poetry is marked by his attention to the spiritual; Josephine Jacobsen, writing for the Nation, observed, “Gregor’s most impressive accomplishment is his ability to make the spiritual intensely apprehended by the senses.” And David Lehman, in a New York Times review of Embodiment and Other Poems (1983), described Gregor’s poetic work as “an enterprise that is frankly Rilkean in its ‘struggle toward absolute verities’ and its emphasis on praise as the poet’s proper activity.”

Gregor has written children’s books, plays, and the nonfiction A Longing in the Land: Memoir of a Quest (1983), in which he wrote of his family’s 1939 flight to the United States. A longtime resident of New York City and France, he moved to France after his retirement to make his home in Paris and the Loire Valley.