But now, in courtroom battles across the subcontinent, in cases brought by slum dwellers and outsourcing workers and millionaires alike, Indians are fighting in growing numbers to divorce. And as words like “alimony,” “stepchild” and “pre-nup” start to roll off Indian tongues, many observers bemoan a profound metamorphosis of values in a nation trotting toward new affluence.

“The great Indian family is definitely under threat,” said Shobhaa Dé, the author of “Spouse: The Truth about Marriage” and one of India’s most widely read social chroniclers. Dé, herself divorced and remarried years ago, described the new ethos as “unthinkable to an earlier generation.”

Consider the microcosm of Mumbai. Since 1990, around the time that India opened its gates to the world, the annual number of divorce petitions filed in Mumbai has more than doubled to reach 4,138 in 2007, far outpacing population growth, according to data culled for this article from musty, hand-kept records at the city’s family court.

Or, to put it more vividly, Mumbai made divorcés of 30,000 more people in those 17 years than it would have had the annual rate of breakups held at the 1990 level.

Such detailed data are not compiled at the national level. But, according to a study of 2001 census data by two Indian demographers, Ajay Kumar Singh and R.K. Sinha, Mumbai’s divorce rate – with about 7 percent of marriages failing – is roughly on a par with that of other metropolises and not much higher than the national level, offering a reliable gauge of the national trend.