Tensions over the South China Sea, a body of water at the center of an international territorial tussle, reached new highs Tuesday after a U.S. Navy ship sailed through contested waters near the chain of Spratly Islands. The long-disputed islands, which are occupied by Vietnam, Taiwan, Philippines, Malaysia, China and Brunei, started getting some new, unwanted neighbors last year after Beijing began building artificial islands in the Sea to house military bases.

China’s aforementioned regional rivals, including Taiwan, claimed that the man-made islands were a way to exert control over international shipping lanes, the rich fishing grounds and possible energy reserves under the seabed. On Tuesday, the U.S. launched an operation in order to demonstrate the right to navigate in the area, which the United Nations has designated as shared, international waters.

Tuesday's actions by the U.S. military in the South China Sea prompted China to condemn the move in the harshest of terms, in what was the most recent in the lengthy, significant series of events.

While the history of occupation on islands in the South China Sea goes back hundreds of years, it wasn't until 1974 that China began strongly exerting itself in the region when it killed dozens of Vietnamese troops that were stationed on a small group of islands in the wider Paracel Islands range, which is just north of the Spratly Islands.

Below is a retrospective of the most significant moments in the dispute, beginning in 2001 and using information provided by the Center For New American Security, a bipartisan global security think tank based in Washington, D.C.