Born on Yancy Street in New York City's Lower East Side, to a Jewish[8] family, Benjamin Jacob "Ben" Grimm had an early life of poverty and hardship, shaping him into a tough, streetwise scrapper. His older brother Daniel, whom Ben idolized, was killed in a street gang fight when Ben was eight years old. This portion of his own life is modeled on that of Jack Kirby, who grew up on tough Delancey Street, whose brother died when he was young, whose father was named Benjamin, and who was named Jacob at birth.[9] Following the death of his parents, Ben was raised by his Uncle Jake (who had married a much younger wife, Petunia, who would become a frequent reference used by the character until her death).[10] He comes to lead the Yancy Street gang at one point.[11]

Excelling in football as a high school student, Ben received a full scholarship to Empire State University, where he first met his eventual lifelong friend in a teenaged genius named Reed Richards, as well as future enemy Victor von Doom.[12] Despite their being from radically different backgrounds, science student Richards described to Grimm his dream of building a space rocket to explore the regions of space around Mars; Grimm jokingly agreed to fly that rocket when the day came.

After finishing college, having earned multiple advanced degrees in engineering,[13] Grimm joined the United States Marine Corps, where he was trained as a test pilot. (His exploits as a military aviator are chronicled to a limited extent in issue #7 of the Captain Savage and his Leatherneck Raiders comic, in a story entitled "Objective: Ben Grimm!") While in the Air Force, Nick Fury orders him to serve as a pilot during a top secret surveillance mission into Vladivostok in the Soviet Union, along with Logan (the future X-Man Wolverine) and Carol Danvers (the future Avenger Ms. Marvel).[14] Following this, he becomes an astronaut for NASA.[volume & issue needed]

The details of his life story have been modified over the years to keep the character current.[citation needed] In the earlier stories, up until the one published in the 1970s, Grimm had served in the air force during World War II and the space flight in which he was transformed into the Thing was an attempt to reach the Moon, occurring at a time before any manned space ship had escaped Earth's orbit.[15] The Captain Savage story mentioned above was set during the Second World War.