There are a couple of answers to this:
A: A lot of people back then were heavily Catholic, the Catholic church claimed that the Earth was flat, while others believed the Earth was round.
B: Back then, obviously they didn't have airplanes or satellites, thus people believed the Earth was flat. The reasoning of this is because, if you were to look outside right now, the Earth does look like it could be flat. (that is because you have to be at a certain level of elevation to see the curvature of the Earth). Eventually though, people started reasoning and came to the conclusion the Earth was round. (They were proven right when aerospace technology came around.)
Answer:
The places might be having the same temperature and climate.
When you give a latitude and a longitude, that nails it down to a single point
on Earth, so it's not possible for a whole country to be right exactly there.
The point 15° N / 105° E is located in far eastern Thailand. It's about 18 miles
southeast of the city of Ubon Ratchathani, 32 miles from the border with Laos,
and 300 miles east-northeast of the capital at Bangkok.
