the political environment.

The environment around them that benefited the richer countries, (cash crops like cotton for example)
Globalization (more interconnectedness with other countries and “advertisement” allowing them to earn more money)
More people= workforce increasing= more money for that country.

All countries have been poor by today’s standards for most of their history and only in the last 100 years or so have any been rich. Countries got rich because they industrialized which make workers more productive and the poor countries have not industrialized yet but many previously poor countries are doing so now and their economies growing rapidly and soon will be rich. One of the things that is still holding some countries back is their population is growing faster than their economy and they are caught in what economist call the Malthusian Trap. Some economist think that the reason it took so long for the Industrial revolution to happen is because Europe was also until the black death reduce the population by 1/3,