Actually, Betty, the song doesn't "show" anything. It's just a song, not evidence of any historical fact.

Talking of historical fact, the Duke of York was anything but a useless twat. He was no battlefield commander, true enough, but as Commander in Chief he was a genuine visionary who created, against incredible odds, an efficient wartime army from the mess that was the post-American Revolution peacetime British Army. This was the army that Wellington led in the Peninsular War and at Waterloo. If it was not for the Duke of York, Arthur Wellesley would never have become the Duke of Wellington.

The rhyme does not, as History teacher suspects, refer to Bunker Hill, but either to the Duke of York's campaigns in Flanders in 1793-94, or possibly to a campaign five years later in Holland.

Edmund