June 4 marks the 1989 Chinese government crackdown on peaceful protesters in Tiananmen Square. Tanks entered the square and soldiers opened fire on citizens outside the square: they are estimated to have killed thousands.
It also marks Tonga’s Emancipation [or Independence] Day, commemorating the abolition of serfdom in Tonga by King George Tupou in 1862, and the independence of Tonga from the British protectorate in 1970.