Mohenjo-daro:
Built around 2500 BCE, this site was incredibly complex and advanced for the time. It is situated in Sindh, Pakistan, and is said to have been home to over 40,000 people. This major urban settlement has signs of city planning, social organization and a draining system.
or they are respectful that not all religions utilize the same calendar...
"When in Rome..."
...I use my own d@$% calendar, and I expect everyone else to accommodate me!!!!!
Darwin has nothing to do with historical timelines.
https://en.wikipedia.org/wiki/Sacsayhuam%C3%A1n
What we're talking about is the Norse settlements leading to the settling of the North American continent. Greenland because of it's proximity to N. America is the reason it's included.