Apparently, she is. And the law was changed just last year to allow royals to marry Catholics. But their children will be ineligible to inherit the throne.
http://www.torontosun.com/2016/11/03/why-meghan-markles-faith-may-be-a-royal-issue
Wills and Kate better have more kids, as insurance !
I went to an expensive Catholic private school and maybe 20% of the kids there were Jewish, just as she is.
Did my going to a Catholic school make ME Catholic? Nope.
Did it make HER Catholic..? Nope.
Okay, maybe officially she converted.