As Dalkeith High did not provide further education, he completed his schooling at Broughton Junior Student Centre in Edinburgh.

[4] In 1936, he received a Doctor of Science (DSc) degree from the University of Edinburgh for a collection of papers on terrestrial magnetism.

[8] On 6 November 1943, he was granted an emergency commission with the rank of group captain in the Royal Air Force Volunteer Reserve;[9] this leant him the necessary authority in a military milieu unused to outsiders.

This would improve the visibility of obstacles on the beach, while minimising the amount of time the men would be exposed in the open.

[16] A major storm battered the Normandy coast from 19 to 22 June, which would have made the beach landings impossible.

[17] As the Luftwaffe meteorological centre in Paris was predicting two weeks of stormy weather, many Wehrmacht commanders left their posts to attend war games in Rennes, and men in many units were given leave.

[18] German Commander Field Marshal Erwin Rommel returned to Germany for his wife's birthday and to meet with Hitler to try to obtain more Panzers.

[23] Stagg was portrayed by Patrick Barr in the 1962 film The Longest Day, Christopher James Baker in the 2004 TV movie Ike: Countdown to D-Day, David Haig in his own 2014 play Pressure,[24][25] and Steven Cree in 2017's Churchill.