I did know that many countries with legal systems in the Roman tradition (including both Argentina and Mexico) have separate civil and religious ceremonies for marriage. My mother showed me pictures when I was a kid of both my aunt and uncle's civil weddings, in formal business dress, and then their church weddings - that concept isn't foreign to me.
But I was surprised yesterday to hear about civil baptism from a French friend with a big family. What's the point? It's not like religious baptism has any legal ramifications.
And, according to Infobébés.com, civil baptism doesn't either:
As for religious baptism, the certificate of civil baptism signed during the ceremony has no legal value.
It's a moral engagement for the godfathers and godmothers with respect to their godchild.
If something happens to the parents, civil baptism creates no legal link between the parties. It's only a moral engagement expressing the godmothers' and godfathers' attachment to this particular child.
That doesn't mean people don't do it - the same article says that most town halls in France will do it for you on Saturday afternoons, even though, by law, a mayor can refuse to participate.
According to Wikipedia, France is the only country that practices civil baptism, going back to the First Republic (late 1700's). It's been practiced off and on, coming back into vogue most recently in the 90's. I can't find much about why one would do it, other than to have a party if the family isn't religious. Or to have real godparents.
For a few weeks in July my boyfriend and I visited a bunch of his family, including his two godparents and his godson (his goddaughter's mother... long story). He mentioned that his godparents were "real," in that he was baptized in the Church, but his godchildren weren't baptized, so they're "fake godchildren."
It reminded me of language many same-sex couples in the US use to describe the need for marriage as opposed to just the rights associated with marriage - yes, marriage is more widely recognized than a civil union, but I can't help but notice that some people want it to be "real," in their terms, which I take to mean "with a sheet of paper from an authority like a church or the state." That sort of thing generally isn't my bag, but you can check out the videos on YouTube under "bapteme civil" and see that it's pretty important to some people.
You can also read the comments on this site and find most people agreeing that the whole thing is stupid since godparents don't have any legal status anyway. While I can't find any statistics on the practice, I'd never heard about it before yesterday after living out here for five years. So I doubt it's particularly common.