Thirty years ago, Chinese troops opened fire on protesters who had gathered in Tiananmen Square, Beijing, killing hundreds if not thousands of people in a massacre that crushed a student-led movement for democracy.

The actions of China’s citizens and the government’s authoritarian reaction in the spring of 1989 have rippled across history, shaping the path party leaders would take the country for the following three decades.

Here’s a guide to our recent coverage of the massacre, and the ways it has influenced China’s government and divided its people.