Wilmot

Song

But all love's soft, yet mighty powers,
  It is a thing unfit
That men should fuck in time of flowers,
  Or when the smock's beshit.

Fair nasty nymph, be clean and kind,
  And all my joys restore
By using paper still behind
  And spunges for before.

My spotless flames can ne'er decay
  If after every close,
My smoking prick escape the fray
  Without a bloody nose.

If thou wouldst have me true, be wise
  And take to cleanly sinning;
None but fresh lovers' pricks can rise
  At Phyllis in foul linen.

John Wilmot, Earl of Rochester, c. Sept. 1680.

Now that's a, er, grounded view of love. But what would you expect from the first poet to publish a poem containing the word fuck.