Namesakes
American Cities:
5 cities
Kingston Massachusetts 
Kingston New Hampshire
Kingston New York
Kingston Pennsylvania
Kingston Rhode Island
British Cities:
1 city
Hull (a.k.a. Kingston) East Riding of Yorkshire
Cities 100K+:
2 cities
Hull (a.k.a. Kingston) United Kingdom
Kingston Jamaica
World Capitals:
2 capitals
Kingston Jamaica
Kingston Norfolk Island (Australia)