The film, of course, telescoped the time line and injected dramatic elements to the story where they were needed. One of the most cheering things to find out was that Logue and the Duke of York were friends pretty much from the start; the plotline of the duke needing to be convinced that Logue's therapy was worth trying was more or less invented for dramatic licence. It is, however, true that Logue was in attendance for the new king's first radio speeches from Sandringham. It was also rather heartwarming to read their continued warm correspondence even after the king no longer needed Logue's professional services.
I thought I spotted a Northern Ireland link, but it turned out to be bogus: in the mid-1920s the comptroller of the Duke of York's household was one Captain Basil Brooke. Was this, I wondered, the future Prime Minister of Northern Ireland? Wikipedia seemed to indicate a gap in his political career in the mid-1920s which was just the right fit; also his highest military rank, achieved in 1920, was Captain. However, further digging revealed that the comptroller was a navy man (and in fairness an exalted naval captain is a more likely candidate for uch a post than a humble army captain), who was Rear Admiral Sir Basil Brooke by 1928. Wikipedia lists two Royal Navy officers of that name and roughly the right age, one born in 188 and one born in 1895, but neither of them seemed quite right - certainly neither was a Rear Admiral in 1928. It turns out that the royal official was yet another naval Basil Brooke, the first cousin once removed of the future Northern Ireland Prime Minister, born in 1876 and living until 1945. His wife Olave is the subject of a painting by Australian artist George W. Lambert, The Red Shawl.