What has been responsible for these remarkable differences in marriage patterns?
In many East and Southeast Asian countries, delayed marriage can be linked to rapid economic development, rapidly advancing educational levels for women and related changes in employment patterns.
But this is no longer the case: over recent decades countries in East and Southeast Asia have seen the demise of universal marriage, and this has directly contributed to declines in fertility in many countries to ultra-low levels because there is almost no childbearing outside marriage.
Yet in other parts of Asia, especially in South Asia, it is not the failure of people to marry that is of concern but the persistence of high levels of teenage marriage, much of it occurring below the legal minimum age.
Almost all women in China are married by the time they reach age 30 — but this pattern is not repeated by ethnic Chinese populations elsewhere in the region (including Hong Kong), which have extreme patterns of delayed marriage.
Interestingly, it is not that women marry very young in China, but rather that marriages are concentrated in the 20s to a much greater extent than in other East and Southeast Asian countries.
Women in the region still prefer to marry up, and men are often reluctant to marry someone who is better educated or makes more money than they do.
To add to these factors, effective matchmaking procedures have not emerged to replace the earlier arranged marriage systems.
This is the case, for example, in Nepal, Bangladesh, and India. Though many countries in East and Southeast Asia now show patterns of very delayed marriage, not all of them do.
The people of Japan, South Korea, Taiwan, Thailand and Myanmar marry late, while the people of Indonesia marry earlier.