Commissioned by the BBC Military Band, the piece is based on Holst's love for the London borough of Hammersmith.

[1] Imogen Holst, Gustav Holst's daughter, writes in her biography of Gustav: Those who knew nothing of this forty-year-old affection for the Hammersmith district of London were puzzled at the title ... Its mood is the outcome of long years of familiarity with the changing crowds and the changing river: those Saturday night crowds, who were always good-natured even when they were being pushed off the pavement into the middle of the traffic ... As for the river, he had known it since he was a student ...

[4]Hammersmith's premiere was performed by the United States Marine Band at the American Bandmasters Association Convention in Washington, D.C., in 1932.

[11] Halfway through this section, the meter in the woodwinds (excluding bassoon and tenor sax) changes to 68, and the remainder of the instruments stay in 24.

Cantrick writes, "floating out of nowhere in the middle reeds and passing on down to the horns, the long-breathed cantilena of the Prelude returns, flooding out everything else.

[14] The piece was dedicated "To the author of The Water Gypsies",[15] the humorist and politician A. P. Herbert, who reflected upon his life along the British waterways in the novel.

Murray Carmack wrote in The Musical Times in 1963: I heard it once, in a BBC broadcast, and thought it a fine work; and think so again reading this score in which the brilliant boisterous pages are controlled by a keen, clear intelligence; and the prelude, central episode and coda evoke, so beautifully, a solitude and peace that can be found in the heart of London's bustle.

[16]Frederick Fennell remarked that, "Hammersmith still represents some of the most treacherous stretches of music making in all of the band's literature.