In 1915, having been a member of Glasgow University Officer Training Corps, he was commissioned into the Argyll and Sutherland Highlanders and served during the First World War with the British Expeditionary Force in France.
[1] In July 1938, Robertson was chosen as Conservative Party candidate for Streatham, a predominantly middle-class area of London where the sitting Member of Parliament (MP) Sir William Lane-Mitchell was retiring.
[2] In the event, the postponement of the general election due to the outbreak of war led Lane-Mitchell to resign by being appointed Steward of the Manor of Northstead in November 1939.
[3] On 26 June, Robertson used a debate in the House of Commons to raise the issue of facilities for troops at London's mainline train stations.
[5] In 1941, Robertson volunteered to take an additional role looking after the interests of the constituency of Peebles and Southern Midlothian, whose Member of Parliament Archibald Maule Ramsay had been detained under Defence Regulation 18B.
At the 1950 general election, Robertson moved constituencies from Streatham to fight Caithness and Sutherland, the northernmost part of mainland Scotland.
The constituency had a long Liberal tradition but the Conservatives had won the seat from Liberal leader Sir Archibald Sinclair in 1945 on a pledge by the candidate Eric Gandar Dower to seek re-election after the capitulation of Japan; as a result of breaking that promise (among other things), Gandar Dower had fallen out with his Unionist Association.
[11] When the site of Dounreay was chosen for a nuclear power establishment, Robertson welcomed the choice and hoped it would lead to repopulation of the highlands.
[16] In January 1959, he seconded an amendment moved by Labour MP Tom Fraser to continue marginal agricultural production grants, but again found Maclay unwilling to help.
[17] This was the last straw and a week later Robertson resigned the whip in protest at the Government's handling of Scottish affairs, declaring he would sit as an Independent Member of Parliament.
[23] He was particularly anxious to serve on the Sea Fish Industry Bill, on which he had immense experience, and other MPs of all parties campaigned for him to be put on the committee.
Their letter of resignation was read at a meeting which unanimously endorsed the candidacy of Maitland, and their departure was described as a "welcome relief" by the chairman of the Thurso Unionists.