He was educated at Fretherne House preparatory school, Westminster and Pembroke College, Cambridge, and was called to the Bar, Middle Temple, in 1913.

Davidson was anxious to serve in the First World War, but Harcourt considered him so valuable that he managed to convince him to stay at the Colonial Office.

In 1915 Bonar Law replaced Harcourt as head of the Colonial Office, and was urged to retain Davidson as private secretary.

[2] In December 1916 Bonar Law was appointed Chancellor of the Exchequer and Leader of the House of Commons and insisted on taking Davidson with him as private secretary.

Baldwin had up until then been an obscure back-bench MP, but his appointment as PPS to Bonar Law was his first move on the ladder of promotion.

In 1918 he was responsible for the final draft of the "coupon" endorsing parliamentary candidates in the general election as representatives of the coalition government.

[2] Davidson entered parliament unopposed for Hemel Hempstead in 1920 by-election[2][3] and became Parliamentary Private Secretary to Bonar Law, then Lord Privy Seal and Leader of the House of Commons.

Despite the wishes of the party leadership, a majority of MP's voted against continuing the coalition at the Carlton Club meeting in October 1922.

Bonar Law, now gravely ill, asked not to be involved, but it was apparent that he favoured Baldwin although he could not overlook the claims of party grandee, Curzon.

The note had been handed over to Stamfordham by Sir Ronald Waterhouse, another of Bonar Law's secretaries, at the same time as his official resignation as Prime Minister.

The King's decision was firmly based on his own good sense and the powerful arguments of Balfour against the choice of a peer as prime minister".

Baldwin once again formed an administration after the brief first-ever 1924 Labour government, and made Davidson Parliamentary and Financial Secretary to the Admiralty.

In this post he was forced to deal with cuts in naval expenditure proposed by the Chancellor of the Exchequer, Winston Churchill, especially regarding the construction of new cruisers.

[2][6] According to Blake, Davidson "left a lasting imprint on the organization of the party, including the creation of the Research Department, and many of the changes attributed to his successor, Neville Chamberlain, were in fact his".

He invited Joachim von Ribbentrop to meet with Stanley Baldwin for the first time in Westminster to discuss Hitler's ideas about equality in armaments.

They had two sons and two daughters:[10] Lady Davidson remained MP for Hemel Hempstead until 1959, and was created a life peer as Baroness Northchurch in 1963.