we refer to as 'The English' and who are credited with it's procurement and establishment, spell it 'colour' as do people from:
Antigua and Barbuda Australia The Bahamas Barbados Belize Botswana Cameroon Canada Dominica Fiji The Gambia Ghana Grenada Guyana India Ireland Jamaica Kenya Kiribati Lesotho Liberia Madagascar Malawi Malta Marshall Islands Mauritius Micronesia Namibia Nauru New Zealand Nigeria Pakistan Palau Papua New Guinea Philippines Rwanda Saint Kitts and Nevis Saint Vincent and the Grenadines Samoa Seychelles Sierra Leone Singapore Solomon Islands South Africa Sudan Swaziland Tanzania Tonga Trinidad and Tobago Tuvalu Uganda United Kingdom Vanuatu Zambia Zimbabwe Anguilla Bermuda British Virgin Islands Cayman Islands Christmas Island Cook Islands Falkland Islands Gibraltar Guam Guernsey Hong Kong Isle of Man Jersey Montserrat Netherlands Antilles Niue Norfolk Island Northern Mariana Islands Pitcairn Islands Saint Helena Tokelau Turks and Caicos Islands
It's the proper way to spell it, if you speak and write 'American' however. Less letters, less spelling mistakes I suppose :)