Editor’s Note: This story contains spoilers for the movie Pressure.
The Allied Forces stormed the beaches of Normandy, France, on June 4, 1944, turning the tide of World War II in what we now know as D-Day. A new biopic highlights how the soldiers battled not only enemy gunfire, but the unpredictability of Mother Nature.
Pressure recreates the critical landing operation in Nazi-occupied France and the less-heralded, but equally important, events preceding it. In theaters Friday, May 29, the movie stars Academy Award winner Brendan Fraser as General Dwight D. Eisenhower and Andrew Scott as Group Captain James Stagg, the meteorologist who consulted on the attack.
Because D-Day—also known as Operation Overlord—required very specific environmental conditions, such as a full moon (aiding visibility for air operations) and low tides (exposing any mined obstacles for ground troops), Allied troops had a very limited three-day window to launch the invasion.
Enter Stagg, whose knowledge of the skies and seas helped Eisenhower avoid a disastrous mistiming.
Who Was James Stagg?
James Martin Stagg was born June 30, 1900, in Musselburgh, part of Scotland’s Edinburgh County, according to the National Records of Scotland. His parents were Alexander Stagg, a plumber, and Helen Martin. James had a younger brother—also named Alexander.
Census records from 1921 show Stagg became an art student, and later graduated with a Master of Arts from the University of Edinburgh. Stagg quickly showed a proficiency for weather forecasting, joining the British Meteorological Office in 1924 and leading a British Polar Expedition to Fort Rae, a remote area of the Northwest Territories in Canada.
By the peak of World War II, Stagg was raising a family with his wife Elizabeth Kidner (played in Pressure by Tamsin Topolski). The couple had two sons: Peter, born in 1941, and Alexander in 1944.
While Stagg didn’t pilot a boat or handle a gun during the war, he singlehandedly saved the Allies from a tactical mistake that could have doomed their chances of victory.
What Role Did James Stagg Play in D-Day?
D-Day is the largest seaborne invasion in history, with nearly 160,000 Allied troops arriving on the Normandy beaches to begin the liberation of France and Western Europe, helping achieve a victory over Germany.
Originally, the operation was planned for June 5, 1944, a Monday. However, Stagg—the Chief Meteorological Officer to Eisenhower—advised the chief Allied commander that strong gales would hit the coast that day and make a successful landing impossible.
Because Stagg didn’t have the aid of modern weather instruments, like satellites and computer tracking models, he greatly relied on surface observations from military and civilian personnel stationed throughout Britain, the rest of Europe, and even at sea. One crucial report from 600 miles west of Ireland showed surface pressure had begun rising, suggesting conditions would clear up just enough for an invasion window on Tuesday, June 6.
In a journal entry documenting his interactions with Eisenhower and other personnel, Stagg wrote of “some rapid and unexpected developments in the situation over the Atlantic” just two days before the invasion.
“A front from one of the depressions has swept further south than expected and will come through the eastern Channel areas tonight: it is nearly over Portsmouth now,” Stagg continued, according to The D-Day Story Portsmouth. “When that front has passed, there will be a period of fair conditions less than 5/10ths cloud, base 2–3000 ft. and reduced winds; this will last till at least dawn on Tuesday.”
Along with other advisers from the Allied Expeditionary Air Force, he concluded “almost perfect visual bombing weather” would be present from Monday evening through early forenoon Tuesday.
Given this information, and fearful any further delay could help German forces uncover the Allied plan, Eisenhower approved the attack for June 6. “Stagg, we’ve put it on again: for heaven’s sake hold the weather to what you have forecast for us,” he said, according to the meteorologist.
What Happened to James Stagg and Dwight Eisenhower After D-Day?
Although there were more than 10,000 Allied casualties, D-Day proved crucial to the Allied war effort. Germany unconditionally surrendered on VE Day, or Victory in Europe Day, on May 8, 1945, and Japan followed within weeks after the atomic bombings of Hiroshima and Nagasaki.
Eisenhower earned a Distinguished Service Medal from both the U.S. Army and Navy and served as the 34th U.S. president from 1953 through 1961.
But, according to the BBC, Stagg received little formal recognition for his involvement in D-Day and the war effort. There are plaques honoring him in Seaford, England, and Dalkeith, Scotland, but the importance of the role he played in helping the Allied powers win the war is not widespread knowledge.
In 1959, Stagg was named president of the U.K.-based Royal Meteorological Society, whose mission is to “advance the understanding of weather and climate and its applications for the benefit of everyone” through research and educational support. He retired from the British Meteorological Office a year later. In 1971, Stagg published a memoir titled Forecast for Overlord about the Normandy invasion. He died on June 23, 1975.
Stagg’s son Peter has campaigned for his posthumous consideration for the Legion d’Honneur, the highest-ranking decoration of France.
“He must have had sleepless nights. It’s hard to imagine the weight of responsibility on his shoulders,” Peter Stagg told the BBC in 2024.
In the meantime, his story has made it to the big screen for new generations to learn of his crucial World War II role.
See Pressure in Theaters Starting May 29
Actor Andrew Scott was drawn to the no-nonsense qualities of Stagg and described him as someone who’s not “immediately affable or likable” but full of integrity at his core, he revealed to People.
“One of the things that I found so wonderful to play about him was that he’s not charming, or I didn’t want him to be charming,” Scott explained. “He was just interested in doing a good job, going and doing the thing, and he’s not gonna bow down to anybody.”
See how Stagg stood up to Eisenhower and his advisers eight decades ago, helping secure an Allied victory, when Pressure hits theaters Friday, May 29. The war drama stars Brendan Fraser and Scott as Dwight Eisenhower and James Stagg, respectively, with Kerry Condon and Damian Lewis in supporting roles.
Tyler Piccotti joined the Biography.com staff as an Associate News Editor and is now the News and Culture Editor. He previously worked as a reporter and copy editor for a daily newspaper recognized by the Associated Press Sports Editors. In his current role, he shares the true stories behind your favorite movies and TV shows and profiles rising musicians, actors, and athletes. When he's not working, you can find him at the nearest amusement park or movie theater and cheering on his favorite teams.
