More than half of the top 100 media professionals in Britain hail from private schools, even though only 7% of Britons are privately educated. Amongst court judges, the figure surges to 71%; in the senior armed forces it approaches two thirds.
Officering in HM Armed Forces is rather a familial affair. There really are such things as “Army families” and “Navy families”.
And one of the ways that British officers are paid is in a substantial subsidy to boarding school fees for their children. So, the combination of inheritance by choice of serving, plus the way the previous generation get paid, leads to a substantial increase, above that of the general population, of public schoolboys in the senior ranks of the services.