Setting up an old iPad2. Receive "Could not sign in." error.

I received an old (factory reset) iPad 2 from a family member and have been trying to get it set up. When I get to the point where I need to enter my apple ID and password, I:

1. Enter my credentials.
2. Tap "next".
3. See a screen that says it could take a few minutes to set up my Apple ID.
4. Am directed to a screen to accept the terms of service/etc.
5. Tap "Agree".
6. Am directed to another screen that says it could take a few minutes to set up my Apple ID.
7. Receive a pop-up error that says "Could not sign in."
8. Tap Okay.
9. Am returned to the screen to enter my credentials, with the username and password still entered.

How can I resolve this? How can I figure out why it could not sign in?