Using the Wikipedia page on National colours, here are countries with the color black on their flag: 
- In Africa: Egypt, Angola, Botswana, Eswatini, Ghana, Guinea-Bissau, Kenya, Lesotho, Libya, Malawi, Mozambique, São Tomé and Príncipe, South Africa, South Sudan, Sudan, Tanzania, Uganda, Zambia, and Zimbabwe	
- In North America: Trinidad and Tobago, Saint Lucia, Saint Kitts and Nevis, Jamaica, Dominica, Barbados, Antigua and Barbuda, and Bahamas	
- Asia: Afghanistan, Brunei, Iraq, Jordan, Republic of Korea, Kuwait, Syria, Timor-Leste, United Arab Emirates, and Yemen
- In Europe: Albania, Belgium, Estonia, and Germany
- In Oceania: Papua New Guinea, and Vanuatu
- Other: Western Sahara, Palestine, and Donetsk People's Republic
In addition, several former countries also have black on their flags.
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