This very old expression has two different but related meanings. The first meaning is ‘with or against one’s will’ and the second is ‘in an unplanned or haphazard fashion’. Today, the second meaning is encountered more often, but its first meaning is the key to its origin. In its original form it appears variously as ‘will ye, nill ye’, ‘will he, nill he’, ‘will we, nill we’ or ‘will I, nill I’ etc, depending on which person of speech is used. The early English word ‘nill’ was simply a contraction of ‘not will’ i.e. n’ill. Thus, ‘will ye, nill ye’ meant ‘will you or won’t you’ implying the will to do something or not. The various forms of the expression, depending on which person of speech was being used, first appear as early as the 11th century. Shakespeare uses it on several occasions, most notably in Hamlet, Act V, Scene I, “If the man go to this water and drown himself, it is, will he nill he, he goes - mark you that. But if the water come to him and drown him, he drowns not himself.” The OED cites the first appearance of its modern form, willy-nilly, from 1608, which was only a few years after Shakespeare’s use of the old archaic form.