Hundreds of Millions. But empires are common in history. The Aztecs and Incas had expansive empires as well--they just could not travel very far because they had no horses.
All governements seem to want to expand. Europeans were just lucky because they had access to domesticated pack animals and horses, various cereal agriculture, and plenty of iron ore to make steel. The steppe peoples of far eastern Asia seemed to enjoy expansion as well: Persians, Avars, Huns, Mongols, Turks, etc. Japan was expansive too until 1945. The expansion of all these world powers ended in the 20th Century thanks to the world wars.
While World War I only killed off the nobility of Europe; World War II killed off Europe itself--including European colonialism. There was no strong country left standing after that war other than the United States (and a broken-down UK and a large, but broken-down, Soviet Union). Since that time, our commercial republic has treated the world as its own personal piggy bank, enlisting the help of European nations that it had helped to re-build after 1945. Since 1945, the US government combined Western Europe's old high-handed methods of colonial governance with our own legal-mind and underhanded robber-baron traditions. Instead of colonizing, we bribed, threatened, stole, impoverished, and occasionally attacked. Our farthest western sphere of influence tried to go beyond eastern China, Guam, South Korea, and Japan; but was stopped dead in Southeast Asia by 1975. Our farthest-east sphere of expansive influence is currently bogging down in Afghanistan and may never extend beyond Kuwait. We might be losing North Africa and the Levant. We have already lost South America and may lose Central America too. When the US collapses, another nation may try to extend an exploiting commercial control over the globe and follow our example, which was the new form of colonialism. I don't know what comes after the US system of control.