I'm not really sure one could call them shorts, more what the British of the 20th century called 'French Knickers', a form of 'Drawers', [ which up to the end of the 19th century was less indecent, the lower garments of Indian coolies etc. being called drawers openly ].
Trouble is the progressive nature of fashion ineluctably makes previous terms of underwear stale and coy.
