During World War II, he covered Europe and North Africa for CBS News.

Collingwood was also among the early ranks of television journalists who included Walter Cronkite, Eric Sevareid, and Murrow himself.

[2] Collingwood covered World War II for United Press in London and was soon recruited to CBS by Edward R. Murrow in 1941.

In 1942, Collingwood was sent to cover the North African Campaign, where he proved his reporting abilities despite being considered "green" as a broadcast journalist.

[4] The other CBS correspondents on the ground, Bill Downs and Larry LeSueur, were not able to deliver reports until days later because of trouble setting up mobile transmitters.

One of his first roles on television was as host of the CBS documentary series Adventure, which was produced in collaboration with the American Museum of Natural History.

The book received critical praise for its merits as a thriller and for its insights into the complexities of the Vietnam War.