William Tyrrell, 1st Baron Tyrrell

[1] He appears to have been one of Grey's few intimates but an inherent laziness and frustration with red tape make an assessment of his influence difficult.

Certainly however Tyrrell played a more important role than his title might suggest and, for example, in the autumn of 1913 he was sent to Washington as a personal ambassador by Grey to discuss the situation in Mexico following the overthrow of Francisco I. Madero.

In the spring of 1915 Tyrrell appears to have suffered an almost total breakdown (perhaps precipitated by the death of his younger son that year) and he was moved to a less stressful job at the Home Office before being made head of the Political Intelligence Department from 1916 to 1919.

As Permanent Under-Secretary he did not think there was a military threat from Japan and that Russia was the enemy and as Ambassador he worked for an Anglo-French agreement.

He died in March 1947, aged 80, when the barony became extinct as both his sons had been killed in the First World War.