On the Tenth Day of Christmas...Ten Lords A-Leaping
Our suitor is getting serious as he is now hiring the entertainment for his lady. The ten lords a-leaping most likely refers to leaping dancers (called morris dancers) who performed between courses at feasts (more eating of the birds). This type of wild and strenuous dancing probably evolved from more ancient war and fertility dances and would have been a popular form of entertainment for this type of function. Unlike the nine ladies dancing in the previous stanza where the dancers appear to have been guests dancing for enjoyment, these were professional dancers brought in to entertain the guests while they dined.
Morris dancing itself was a popular form of folk dancing in the fifteenth and sixteenth centuries. Both King Henry VIII and his daughter Queen Elizabeth I had professional morris dance troupes perform as part of the entertainment at feasts. Many parish church records from this period show both expenses for the purchase of costumes and the bells that the dancers wore while performing as well as income from the rental of the costumes to neighboring parishes. Morris dancing declined following the English Civil Wars of the mid-seventeenth century which brought Oliver Cromwell and the Puritans to power with their dislike and banning of any type of frivolity such as singing and dancing. The twentieth century brought a revival of the morris and other folk dancing traditions in the UK and other parts of the world including the U.S. Today there are local morris dance troupes and competitions in the UK as well as other parts of the world.
Only eight lords a leaping, but it will give you and idea of the Morris Dancers