I used to live and work in Florida but moved back to my home country Germany. I still have a "normal" IRA and am now over 59 1/2. Do I have to pay taxes on distributions from the IRA in the US? I do not have any other income there.

Yes, you WILL have to pay normal income taxes on the IRA distributions.

You will receive Form 1099-R that shows the IRA distributions for the caledar year. That distribution amount will be reported on Form 1040NR, and the appropriate tax levied (probably at 10-15%).