Supposedly, a 1288 law by Queen Margaret of Scotland (then age five and living in Norway), required that fines be levied if a marriage proposal was refused by the man; compensation ranged from a kiss to £1 to a silk gown, in order to soften the blow.[8] Because men felt that put them at too great a risk, the tradition was in some places tightened to restricting female proposals to the modern leap day, 29 February, or to the medieval leap day, 24 February.
(snip)
Women looking to take advantage of their opportunity to pitch woo were expected to wear a scarlet petticoat -- fair warning, if you will."[9]
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In Denmark, the tradition is that women may propose on leap day 24 February and that refusal must be compensated with 12 pairs of gloves.
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