There is a surprising (at least to me initially) amount of lesbianism in early modern stuff, and (obviously less surprisingly) in modernist stuff (a female doctor even wrote RPF of theLadies of Llangollen, which has been recently reprinted in a nice bright pink volume). It's less prominent in Victorian literature (I think — still have a lot of reading to do), but lesbians do still show up here and there, and there's even a Welsh novel with a lesbian main character.