Is there such a law that says that they cannot "nuke" last names once
they get them, but are only allowed to "pile on" the new one to the
ever-growing list of last names? Perhaps as a way to signal that it's
not a good idea to get married to somebody who's obviously prone to
If this is not the case today, has it been the case in the past? I
wonder about this both for the USA and the Western world in general.
I am aware of no such law, either today, or in the past, in the U.S.A. or the Western world.
In the Spanish language speaking world, it is often customary for a child to be given the surnames of both parents and it is not unprecedented for that to continue for more than one generation, which can result in very long names.
It is also common place for members of royal families and high aristocrats to have very long names, only a handful of which are used on a daily basis or in governmental roles, so as to grant symbolic acknowledgement of many people after whom a royal or high aristocrat is named.
Also, keep in mind, that divorce isn't particularly old in the Western (historically Christian) world (divorce was permitted in Islam from its inception in the 7th century CE). Prior to the formation of the Anglican Church, from roughly the 10th century CE until the 17th century CE divorce was almost completely prohibited in all of Christian Europe (although annulments were recognized as was "separation from bed and board" while remaining married).
Divorce had to be expressly authorized on a case by case basis by the legislature in the Protestant countries that legalized it, in almost all of the Western world, until the 19th century. Legislative divorces were exceedingly rare and all rules applicable to them were decided on a case by case basis. I am not aware, however, of any mandatory multiple surnames arising from legislative divorces.
There was also roughly a century in England prior to the institution of judicial divorces where the practice of wife sales in lieu of divorce and remarriage was recognized. See Boettke, et al. "Wife Sales", 1 Review of Behavioral Economics 349-379 (2014). But, in that era, the use of surnames for commoner women in England wasn't even firmly established.
Judicial divorces started to be authorized in most Western countries, including most U.S. states, in the 19th century. Some Western countries didn't legalize judicial divorce until the 20th century. Ireland and Italy were particular late in doing so.
Surnames also weren't firmly established as something used by common people for a long time in many Western nations even when they started to be used by the upper classes and aristocrats, and where they were used, a period of patronymics and matronymics often preceded the use of fixed surnames inherited from parents to children (e.g. in Russia and Scandinavia), with some countries that went through the intermediate stage of patronymics and matronymics often not adopting the latter form of fixed surnames until the 19th century.
By 1400, most English and some Scottish people used surnames, but many
Scottish and Welsh people did not adopt surnames until the 17th
century, or later. Henry VIII (ruled 1509–1547) ordered that marital
births be recorded under the surname of the father. In England and
cultures derived from there, there has long been a tradition for a
woman to change her surname upon marriage from her birth name to her
husband's family name. The first known instance in the United States
of a woman insisting on the use of her birth name was that of Lucy
Stone in 1855; and there has been a general increase in the rate of
women using their birth name. This has gone through periods of flux,
however, and the 1990s saw a decline in the percentage of name
retention among women. As of 2006, more than 80% of
American women adopted the husband's family name after marriage.
Even when divorce was forbidden, remarriage wasn't particular uncommon, however, due to remarriage by widows and widowers. In the pre-modern era, however, except in times of war, widowers remarrying due to the death of wife in child birth was more common than widows remarrying, and husbands typically did not change their names upon marriage or divorce.
Typically, in the era of judicially granted divorces, the law allowed for a change of name upon divorce, allowing a divorcing women to reclaim a maiden name or other premarital name if desired, but also to retain a married name from prior to the divorce. When a married name is kept after a divorce, it is typically done to retain a shared identity with the divorced women's children who typically bear her husband surname.
Typically, the law also provided for a change of name upon a woman's marriage, either voluntarily, or by operation of law, to her husband's name, and later, in more liberal eras, to a hyphenation or double surname, or to a new name all together. At times it has been common for a married woman to use her maiden name as a middle name, in addition to, or in lieu of the middle name she was given at birth.