The leisure activity glamping is first attested in The Guardian in 2005, a portmanteau of glamorous and camping. Popular usage had spread to American English by 2007. As with many of this century’s coinages, the concept of luxury camping existed before, but there wasn’t a specific word for it. (Maybe safari, but that now has other connotations due to semantic drift.) For example, this trend’s rise in popularity begins in the 1990s.