It's a song by Australian folk group The Waifs, about the war brides who made the trek from all across Australia after WW2 to meet the SS Monterey, which took them to the US to reunite with their husbands.
Well my grandmother & mom were on that very same crossing, on the Monterey.
Here's a bit about the SS Monterey. It's Wikipedia, so don't take as a primary source, but a starting point, & check additional sources. https://en.wikipedia.org/wiki/SS_Monterey