Mail not working outside of the US

Question

Why was I unable to send or receive email using the Apple Mail app on my iPhone and iPad (both had iOS 8.1.2) when traveling outside the US last week? The email accounts were functioning fine with Mail within the US. I was connected to secure WiFi networks in Mexico and Ireland. I was able to send/receive email if I bypassed Mail and signed on to each email account directly.

Answer 1

At this point, it sounds like it would be best to delete the email account and then re-add it again.
(the steps are also listed below)
Remove a Personal (POP / IMAP) Account - DROID INCREDIBLE 2 by HTC
From a home screen, select the applications tab (located in the lower left).
Select Mail.
From the preferred account, select Menu.
 To change accounts, select Menu > Account list then select the account.
Select More.
Select Settings.
 Not available from All accounts.
Select Delete account.
Select OK.  
Add a Personal (POP / IMAP) Account - DROID INCREDIBLE 2 by HTC
Server addresses, security information and additional support can be obtained from the email provider.
From a home screen, select the applications tab (located in the lower left).
If performing Initial Activation and Setup begin with step 2.
Select Mail.  
Yahoo, Windows Live Hotmail, AOL and Gmail
Enter the Email address and Password then select Next.
Ensure the following are correct.
Account name
The name of the account on this device.
Your name
The from name for mail sent from this account.
Select Make this my default mail account to enable / disable.
Enabled when a check mark is present.
Select Finish setup. 
Please let me know if this doesn't work for you.