There are a host of political and cultural reasons for the delay. Eric Pape points out in Foreign Policy that, though France decriminalized homosexuality in 1791 -- ahead of many other countries -- it has also had a pretty vocal Roman Catholic population, a fairly anti-gay conservative government in the early part of the 20th century and a more recent wave of colorful anti-gay pundits. There have been scores of family-minded -- but not necessarily religious -- protesters, who've waved signs reading "un papa. une maman" and seemed mostly concerned about the idea of gay adoption.
“In moral terms, there is a kind of precautionary principle for some — let’s not go too fast or too far or be too radical," Dominique Moïsi, a French political analyst, told the New York Times.
Former French president François Mitterrand kept a separate, secret family with longtime mistress Anne Pingeot, who attended his 1996 funeral alongside Mitterrand's wife.
Former president Jacques Chirac's memoirs alluded to similar encounters: “There have been women I have loved a lot, as discreetly as possible,” he wrote.
More recently, former International Monetary Fund chief Dominique Strauss-Kahn's high-stakes cheating cast a light on the "sex parties" of Paris. “I long thought that I could lead my life as I wanted,” he said in an interview with the French magazine Le Point. “And that includes free behavior between consenting adults."
For decades, it was accepted that France's homosexuals would do whatever they wanted in private -- just as married men and women would. But once the effort to formalize homosexual relationships gathered strength, there was some push-back from a public that was accustomed to keeping sex lives in the shadows. (One French journalist described a scene at a metro stop where anti-gay-marriage leaflets were being distributed at the entryway, while ads for extramarital dating sites were displayed all over the platforms.) Pape writes:
Back in the day, officially heterosexual married couples could also have gay flings -- and to this day, some still do -- but an element of French society encourages discretion even now, the core idea being that your sex life is your own and isn't for the public space.
But the country's ubiquitous infidelity has been used to bolster arguments for gay civil unions by their proponents. In November 2012, French journalist Christophe Barbier, the managing editor of center-right magazine L’Express, declared that marriage itself is an “obsolete institution," adding, “In the era of globalization and of the fulfilled and mobile individual, this norm [of marriage] is as artificial as it is inefficient, as shown by the fact that divorce has become commonplace."
The socialist government and increasingly progressive French public undoubtedly made it easier to push gay marriage through, but the introduction of civil unions 1999 might have been the true catalyst for taking French homosexual relationships out of the closet and into the chapel. Those civil unions were also controversial at the time of their implementation but later gained widespread support.