[2] Astor was British Public Schools rackets champion in 1904–1905, spent a year at Oxford, and finally, in 1906, joined the 1st Life Guards.

[5] At the start of 1918, he was put in command of the 520 Household Siege Battery of the Royal Garrison Artillery, his bravery with that unit earning him the rank of Chevalier in France's Légion d'Honneur.

In September that year, near Cambrai, his right leg was shattered by a shell and later amputated,[2] though he was still able to play and win against younger opponents at squash on a prosthetic limb.

[2] Upon his father's death in 1919, Astor inherited Hever Castle, near Edenbridge, Kent, where he lived the life of an English country gentleman.

In March 1924, Astor caused the 1924 Dover by-election to be held after having voted before taking the oath of allegiance - doing so means an MP's seat is vacated "as if he were dead".

During World War II, he also became Lieutenant-Colonel of the 5th Battalion, City of London Home Guard, a unit drawn from newspaper employees,[8] between 1940 and 1944.

In 1953, he had The Times sponsor Edmund Hillary's expedition that made the first successful climb to the summit of Mount Everest and became the first chairman of the newly-established General Council of the Press, a post he held until resigning due to ill-health in April 1955.

[1] Selected artworks from the family's vast collection were bequeathed to the National Gallery including the prized "Thames below Westminster" by Claude Monet.