In 1947 Chifley gained formal agreement from
George VI for McKell's appointment as governor-general. This occurred only after very considerable opposition from the King and a detailed correspondence between them, also involving the incumbent governor-general (George's brother, the
Duke of Gloucester) and the British Foreign Office, the details of which did not come to light for over 50 years. The objection was not personal (George VI had never met McKell) but centred on his being closely associated with a particular political party, and with a particular state. There was no precedent for a serving Australian politician, let alone a party leader and head of government, to be named governor-general, although there was a South African one and several former governors-general had strong ties with British political parties. In the end, the King had no option but accept Chifley's assurances of McKell's personal integrity and that the Crown would not be exposed to any political controversy. Chifley was determined that the
Duke of Gloucester's successor should be a native-born Australian, and he seems to have deliberately chosen a Labor man with a working-class background to make a political point. There was an outcry from the
Liberal opposition and the conservative press:
Robert Menzies called the appointment "shocking and humiliating". In a debate on a censure motion on 20 February, Menzies said the fact that McKell was actively engaged in politics when the appointment was announced (even though he had since vacated the political stage) was "a grave disqualification" which "strikes at the very foundation of the office of the governor-generalship, because that office in Australia should be as far removed from party politics as is the Crown itself in Great Britain". Chifley, in response, accepted full responsibility for the appointment, said that he offered no apologies, and "I am completely confident that as time goes on I shall have no reason to regret my action". McKell kept a dignified silence on the matter of his appointment, rather than conducting a public defence of it. Nevertheless, Chifley publicly argued that any suitable Australian should be capable of being chosen as governor-general. Once McKell took office on 11 March, however, the continuing respect for the Crown and its representative meant that there was no further criticism. McKell carried out the usual round of his formal duties with dignity, behaved with unfailing respect towards the King himself, and succeeded in winning over all but the most inflexible. When Menzies succeeded Chifley as prime minister in December 1949, his relations with McKell were initially civil rather than friendly, but later on, the two men formed a cordial working relationship. Menzies even extended McKell's term by 14 months from its initial five years. On 13 November 1951, McKell accepted a knighthood (
Knight Grand Cross of the Order of St Michael and St George) from George VI, who personally invested him at Buckingham Palace while McKell was on an official visit to the United Kingdom. This caused considerable controversy in the Labor Party, as it was Labor policy to have nothing to do with knighthoods (a policy confirmed by the case of Queensland union leader Sir
Jack Egerton a generation afterwards); but there was nothing Labor could do about it, since McKell had severed all connections with the party on assuming office. Also it was unprecedented and was still considered somewhat inappropriate, for a governor-general not to be at least a knight (many had been peers). McKell was the only Australian governor-general to be knighted during his term, until
Quentin Bryce was appointed a
Dame of the Order of Australia in March 2014. McKell's
official secretary for the first few weeks was Sir
Leighton Bracegirdle, whose retirement was overdue after serving McKell's three predecessors over 16 years. He was succeeded by Sir
Murray Tyrrell. ==Later life==