The June observance circulates through community and local-government proclamations, advocacy groups and holiday-listing sites rather than through a single establishing act, and the Black Lives Matter organisation itself promotes a Black Lives Matter Day on 13 July rather than a June month. It draws on the movement, which Encyclopaedia Britannica and the movement's own organisation date to 2013. No documented founder or formal proclamation for the month appears in primary sources.
A name born from an acquittal
The phrase entered American politics on a specific date. On July 13, 2013, hours after George Zimmerman was acquitted in the killing of Trayvon Martin, the Oakland activist Alicia Garza wrote a Facebook post that ended with the words "Our lives matter." Her friend Patrisse Cullors reshared it with a hashtag, and Opal Tometi joined them to build a network, according to HISTORY's account of that day.
The trigger had come more than a year earlier. Trayvon Martin, an unarmed 17-year-old, was shot and killed in Sanford, Florida, on February 26, 2012. Britannica records that Zimmerman, a neighborhood-watch volunteer, was acquitted in July 2013 in a verdict widely perceived as a miscarriage of justice.


