What happened on July 11 ?

United Nations - World Population Day

Flanders, region in Belgium (not a public holiday) - Flemish Day (1302 Battle of the Golden Spurs)

Ireland - National Day of Commemoration held on nearest Sunday to this date (see Irish calendar).

Mongolia - Naadam Holiday

China - China National Maritime Day

Feast Day of Saint Olga (first Russian Saint)

Feast Day of Saint Benedict (founder of the Benedictine Order)

United States: Free Slurpee at 7-Eleven (most locations do this - get a free 7.11oz Slurpee on 7-11).

Bonfire night in Northern Ireland, precursor to The_Twelfth