England, Scots and Ireland – Charles II Stuart, age 36

Republic of the Seven United Netherlands – Grand Pensionary Johan de Witt, age 41

France – Louis XIV, age 28

Spanish Empire – Charles II Habsburg, age 5

Portugal – Afonso VI, age 23

Denmark-Norway – Frederick III, age 57

Swedish Empire – Charles XI, age 11

Brandenburg-Prussia – Elector Friedrich Wilhelm, age 46

Holy Roman Emperor/Bohemia-Hungary – Leopold I Habsburg, age 26

Polish-Lithuanian Commonwealth – Jan II Kazimierz Vasa, age 57

Tsardom of Russia – Alexei I Romanov, age 37

Ottoman Empire – Mehmed IV, age 24

(To the extent possible, all are portrayed in paintings executed in or around the year 1666.  Charles of Spain shown at the age of 10, Frederick III probably in his 30s, Mehmed IV and Alexei I in undated standard portraits.)