Economic powerhouses like the United States, China and Japan may be home to the highest proportion of the world's wealthy, but when it comes to minting new millionaires, opportunities abound in some surprising places.

That's according to a new report from wealth research firm Wealth-X, which found that the countries on track for the fastest growth in their wealthy populations are select emerging nations across Africa, Asia and Europe.

The study, taken from Wealth-X's inaugural "High Net Worth Handbook 2019," drew on research from more than 540,000 high net worth individuals — those with a net worth of $1 million to $30 million — to forecast its outlook for global wealth growth over the next five years. It took into account current wealth levels, population growth estimates and anticipated future investment opportunities.

The report found the West African nation of Nigeria to be the front runner, set to see its high net worth population balloon by a compound annual rate of 16.3 percent between now and 2023. It was followed by Egypt at 12.5 percent and Bangladesh at 11.4 percent.

Here's the full list of the 10 fastest-growing high net worth countries: