Marriage was quick, easy and difficult to prove
Marriages between men and women of the elite – after all, same-sex unions were most definitely frowned upon by the Medieval church – were usually carefully thought-out affairs. Planned well in advance, they were usually designed with some political or monetary aim in mind. The happiness of the couple was often not a consideration at all. Among ordinary folk, however, things were quite different. Here, things were a lot more spontaneous. So spontaneous, in fact, that it might often be hard to prove that you were actually betrothed!
Quite simply, in the Middle Ages, if you and a loved one wanted to get hitched, all you needed to do was declare yourselves married there and then. No need for a ceremony or even a priest. As you can imagine, such spur-of-the-moment unions were often carried out in the heat of the moment. Sex before marriage was largely condemned in Medieval society, so a couple caught up in a moment of passion would simply declare themselves to be man and wife and then get down to business.
Of course, unscrupulous men could take advantage of the situation. Again, there was no need for a marriage to be witnessed, so if you were a woman in the Middle Ages you ran the very real risk of falling foul of a scoundrel who took you as his wife in order to get you into bed chamber and then, once he had had his satisfaction, denied ever agreeing to the union. Most women, then, did try their best to ensure that their comings together were witnessed, even if only by members of their own families rather than by members of the clergy.