I was trying to import a .csv of Lead data into salesforce today. Salesforce’s import tool is terrible and you have to use something from the AppExchange to get error messages. You’ve probably already discovered that if you’re reading this post.
Anyways, I found that the issue with trying to import any data with a country outside of the United States was because the Country and State Picklists had the United States set to the default country. I changed that default to “none” and the exact same import file ran flawlessly.
I hope this saves someone else some time someday.