The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Revolutions of 2008 - 2014 (2 members)
- Revolutions of 2010 - 2014 (1 member)
- Revolutions of 2010 - 2015 (2 members)
- Rojava (2 members)
- Romania (2 members)
- Russia (25 members)
- Russian Civil War (8 members)
- Russian Empire (6 members)
- Russian Revolution (4 members)
- Rwanda (1 member)
- SAC (5 members)
- Saudi Arabia (2 members)
- Scandanavia (15 members)
- School (1 member)
- Schools (1 member)
- Science (4 members)
- Scientists (6 members)
- Scotland (1 member)
- Second Arab Spring (1 member)
- Serbia (1 member)
- Sex (1 member)
- Sex Workers (1 member)
- Sexual Liberation (1 member)
- Seychelles (1 member)
- Shipping (1 member)
- Silvia Federici (1 member)
- Simple living (1 member)
- Singapore (1 member)
- Situationism (1 member)
- Slavery (1 member)
- Slovenia (1 member)
- Social Centers (2 members)
- Social Democracy (3 members)
- Social Democrats (1 member)
- Social Ecology (1 member)
- Social Movements (25 members)
- Social anarchism (2 members)
- Socialism (3 members)
- Socialist States (5 members)
- Socialists (4 members)
- Societies (24 members)
- Sociologists (2 members)
- Sociology (1 member)
- Soldiers (2 members)
- Solidarity (UK) (3 members)
- Solomon Islands (2 members)
- Somalia (2 members)
- South Africa (4 members)
- South America (32 members)
- South Korea (5 members)