• Leaders of political parties by former country (3 C)
• Socialist parties by former country (4 C)

B

• Political parties in the Byelorussian Soviet Socialist Republic (8 P)

C

• Political parties in Chechnya (4 P)
• Political parties in Czechoslovakia (12 C, 40 P)

D

• Political parties in the Free City of Danzig (3 P)
• Political parties in the Donetsk People's Republic (5 P)

E

• Political parties in the Empire of Japan (1 C, 62 P)

G

• Political parties in the German Empire (1 C, 27 P)
• Political parties in East Germany (3 C, 27 P)

I

• Political parties in the Kingdom of Iraq (3 C, 17 P)

K

• Political parties in Korea (8 C)

M

• Political parties in Manchukuo (4 P)
• Political parties in the Memel Territory (1 C, 5 P)

N

• Political parties in the Netherlands Antilles (7 C, 1 P)

O

• Political parties in the Ottoman Empire (5 C, 17 P)

P

• Political parties in Mandatory Palestine (2 C, 23 P)
• Political parties in the Second Polish Republic (4 C, 26 P)

R

• Political parties in Rhodesia (4 C, 21 P)
• Political parties in the Kingdom of Romania (5 C, 66 P)
• Political parties in the Russian Empire (8 C, 15 P)
• Political parties in the Russian Soviet Federative Socialist Republic (4 C, 26 P)

S

• Political parties in the Saar Protectorate (2 P)
• Political parties in the Kingdom of Serbia (5 P)
• Political parties in the Soviet Union (4 C, 10 P)

T

• Political parties in the Free Territory of Trieste (2 P)

U

• Political parties in the Ukrainian Soviet Socialist Republic (2 C, 25 P)

W

• Political parties in the Weimar Republic (5 C, 43 P)

Y

• Political parties in Yugoslavia (7 C, 28 P)
• Political parties in the Kingdom of Yugoslavia (27 P)