Why did japan and china got such a high population.

China has the largest population in the world, with a shocking number of 1.3 billion people and growing by the minute. ... Overpopulation in a country is the result of the number of people in an area being much higher than the country's available resources.

And for Japan, the Japanese population grew steadily throughout the 20th century, from around 44 million in 1900 to 128 million in 2000. The gains were primarily due to increased life expectancy, but also buoyed by families that typically had at least two children. ... By median age, Japan is the oldest large country in the world.

But that my opinion though.

the american rail road was the most influential and useful transportation system developed in the 1800's with steam locomotives and in the very late 1800's and early 1900's diesel electric locomotives being used to transport goods and people around the newly expanded united states!

in 1862, president lincoln's emancipation proclamation opened the door for african americans to enlist in the union army. although many had wanted to join the war effort earlier, they were prohibited from enlisting by a federal law dating back to 1792.

explanation: