You can help the Chagossians return to their island in the Chagos Archipelago in the Indian Ocean by signing this petition on the White House website:
A few decades ago, the British leased the island to the US. In the process, the inhabitants were displaced to make way for a US base. This was one of the bases used to carpet-bomb Afghanistan and Iraq.
The Chagossians went to court against the British government to get their home back. They were unsuccessful and under the helm of Gordon Brown, the government decided to create a protected marine park there in the hope that the environmental lobby will be powerful enough to keep the Chagossians off the island. The creation of the marine park is now in question.
Meanwhile, the islanders are now turning to the US government o help get justice done. You can help them simply by signing this petition to help gather more than the 25000 signatures needed. The deadline is on the 4th of April.