Poland also votes on Sundays (although some referenda have been 2-day affairs). And I'm pretty much sure, it was never allowed to vote here without an ID.
For ID, two intersecting forces in the UK (and I'd imagine the US is somewhat similar but not the same)
1. Culturally not needing ID is important. That's lessening, but certainly in my age group there's a considerable amount of people who do not want to be asked for ID because it's an infringement on their liberty.
2. Vote suppression. By choosing some documents (more likely to be held by your supporters) as valid ID, and others as not (make up any excuse) you can ensure your supporters aren't turned away at the polls while other party supporters are, this effectively disenfranchises them but you can pretend it wasn't on purpose.
> 2. Vote suppression. By choosing some documents (more likely to be held by your supporters) as valid ID
I'd say the European assumption would be that there are one or two valid ID cards (a passport and a national identity card), and owning either one would be mandatory. Doesn't then disenfranchise anyone.
It's not mandatory in all European countries though. But I think it's usually mandatory that you are able to identify yourself somehow.
The UK does not have a "national identity card" and attempts to introduce one were... lets say not a political triumph.
The main way you might be required to identify yourself in the UK is if a Police Officer says either you are suspected of a specific crime, or you are a witness to such a crime. In both cases officers are entitled to you truthfully revealing your name and address as part of investigating the crime, but they aren't entitled to see a photo ID as you may not even own such ID. If you refuse to identify yourself in either of these cases, or the officer believes your answer was deceitful, they can arrest you (which if you were a suspect was likely going to happen anyway).
in the uk you will effectively need a photo id (passport, driving license etc.) i had to get a passport in order to sell a flat i had owned for 30 years (i needed no id to buy it). the whole anti-money laundering thing has gone mad here.
Same in Spain, and there is a single national ID that everybody is required to have, so there is no problem of rejecting voters based on ideological differences.
I'm also baffled how that is a problem in UK/US.