"Jumping the broom" is an informal marriage or "partnership." It comes from peasant or
gypsy marriages before the idea of a "civil marriage" (going before a justice of the
peace to vow marriage oaths) came about in Britain with the Marriage Act 1836 - as an alternative to a
church marriage.
The concept started in
France as <i>mariage sur le croix d'un epee</i> ("marriage on the cross of a sword") which a maudit anglais (Englishman) translated from a French book as "leaping over a broomstick." The original concept comes from ancient military weddings - when a soldier marries one of the women who hung around soldiers back in the day:
"A sword being laid down on the ground, the parties to be married joined hands, when the corporal or serjeant of the, company repeated these
words: <b>Leap rogue, and
jump whore, And then you are married for evermore.</b> Whereupon the happy couple jumped hand in hand over the sword, the drum beating a ruffle; and the parties were ever after considered as man and wife."
My old Cajun stepdad took me aside after I brought the girl I just proposed marriage to home to meet him and
Mama, and asked "You can'
t just
go jump the broom?", so I'm here to tell you this expression is for real and old farts like him were still using it.