I'm afraid the fox as an animal motif is second only to bears or cats - they're everywhere.
In addition to the song her shirt promoted, there's Elton John's The Fox, Steeleye Span's the Fox (and Album), there's a Czech opera called 'the Sly Little Vixen' (don't ask me to spell it in Czech!)
In folklore, the Fox is almost always a 'trickster' and shows up in tales from Finland, Scotland, France, Germany, Greece, and China (where in one story he's actually a shape-changer) - indicating maybe that the whole thing is a trick to make us all crazy?
I don't know enough about Ottoman or Malian leaders - were any of them nicknamed 'The Fox'? The epithet was applied to several rulers and diplomats in Europe...