German marriages held in London in 1905? #germany #unitedkingdom

This is mostinteresting, because we also have an unexplained marriage involving Berlin. My husband's grandparents were students at the University in Berlin in 1897. They had moved from Warsaw. We have a marriage announcement card that says that they were married in Belin in June 1897.  We have an official wedding license from Geneva Switzerland with a date of September 8, 1897.  We have been unable to figure this out.  Any ideas?  
Avivah R. Z. Pinski ,  near Philadelphia, USA

Corinna Woehrl (nee Goslar)

Dear list readers,

I don't remember any law contradicting a marriage with foreigners: I guess that they didn't have all the necessary documents and perhaps in London less paperwork was required.
I would like to pass the question on to a german-genealogy Mailinglist specialized in the area of Berlin. I will hopefully come back with more information.

Perhaps you could give me more details on the couples (via private mail)? How old were the bride and groom: perhaps the age of maturity was relevant (Germany then 21)?
It would be helpful to know if the problem only occurred with marriages involving Galician Jews.

Kind regards from Germany
Corinna Wöhrl, Hoisdorf (near Hamburg)