A candle lighting ceremony in London is to take place on Thursday commemorating the 75th anniversary of a Nazi-era massacre of Jews in the Iraqi capital of Baghdad.

Organisers say that 27 candles will be lit to symbolise the 27 centuries of Jewish life in the historic city, which all but came to an end after 180 Jews were killed by the pro-Nazi Farhud in 1941 in what is still a little-known pogrom.

Alongside London, which has a large Iraqi Jewish community, candles will be lit around the world, including on Capitol Hill in Washington, D.C. and at the Knesset (Israeli parliament) in Jerusalem.

Harif UK says Iraqi Jewry is the world’s oldest diaspora, but the event “shook the community to its very foundations” and heralded the exodus of 850,000 Jews from Arab lands.

Thursday’s event, which is supported by the Israeli Embassy and campaign group StandWithUs, will be attended by “a senior Israeli diplomat” and feature speeches and readings.