People will marry if they cross paths enough.
Lots of Igbo women live outside SE so more likely meet men of other tribes.

Yes, Igbo women are very pretty and beauty attracts men of all tribes.

Igbo of any gender can spot potential in people. Having money helps too. Relatives married to Igbo women are about the wealthiest.

It's either wealth attracted those Igbo women, the women helped in building the wealth or both.
This applies to men of other tribes too.

I have always liked real estate; farm land, pasture land, timber land and city property. I have had experience with all of them. I guess I just naturally like ‘the good Earth,’ the foundation of all our wealth.”
-Jesse H. Jones,

Land monopoly is not only monopoly, but it is by far the greatest of monopolies; it is a perpetual monopoly, and it is the mother of all other forms of monopoly.”
-Winston Churchill

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