How do I get the EU V sign up bonus?

All you need to do is head over to this page, scroll to the bottom and sign up for the newsletter. Once you've confirmed your subscription you'll get the following message:

To verify that you are subscribed and going to get the Monumental Bonus do the following:

1. Login to your account at https://accounts.paradoxplaza.com/downloads and scroll down
2. If you see the Europa Universalis V Wallpaper Sign Up reward entry, you're signed up and will get the above bonus content as well

If you don't see the wallpapers it means that the sign up has not gone though and you need to do the following:

1. Go to https://beta-accounts.paradoxinteractive.com/profile
2. Make sure Emails from Paradox Interactive is marked green (if it's not, click it, then click save)
3. You will get a confirmation email, click the button in said email
4. Now go back to the EUV page, click subscribe and you should see the image above
5. Once that's done, go back to https://accounts.paradoxplaza.com/downloads and check if you see the EUV wallpaper sign up reward. Please note that it can take up to 24 hours for the subscription to be applied!