Does the FAA require a rating for night VFR?
There's no separate night rating or endorsement in the US, it's included in the private pilot flight proficiency requirements (14 CFR 61.107) and the specific required experience is in 14 CFR 61.109:


  (2) Except as provided in §61.110 of this part, 3 hours of night
  flight training in a single-engine airplane that includes—
  
  (i) One cross-country flight of over 100 nautical miles total
  distance; and
  
  (ii) 10 takeoffs and 10 landings to a full stop (with each landing
  involving a flight in the traffic pattern) at an airport.


Some very minimal instrument training is also required, which can be helpful at night:


  (3) 3 hours of flight training in a single-engine airplane on the
  control and maneuvering of an airplane solely by reference to
  instruments, including straight and level flight, constant airspeed
  climbs and descents, turns to a heading, recovery from unusual flight
  attitudes, radio communications, and the use of navigation
  systems/facilities and radar services appropriate to instrument
  flight;


That all applies to private pilots; sport pilots may not fly at night. And as David pointed out, there is an exception to the night requirements under 61.110 for pilots in Alaska: they can skip the night training but if they do, they can't fly at night.