Withycombe's earliest example in England is from 1646; but the name was used by women there earlier. It was, however, never common in any culture, certainly not as common as its masculine counterpart.
Cite as: J. Uckelman, S.L. Uckelman. "Louisa". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2015, no. 2. http://dmnes.org/2015/2/name/Louisa.