June 19, 1865:Juneteenth

Strictly speaking, Juneteenth has a fairly low presidential content, but there is a connection. It marks the day in 1865 when the Union army started enforcing the Emancipation Proclamation, an initiative of the president, in Texas; the proclamation specifically applied to areas "in rebellion" on January 1, 1863, which included Texas. Afterwards, Juneteeth evolved into a celebration among the black population of Texas and a few other places. It became a state holiday in Texas in 1980, and 13 other states have followed suit in making Juneteenth a holiday.

From the Handbook of Texas Online:"On June 19 ('Juneteenth'), 1865, Union general Gordon Granger (pictured) read the Emancipation Proclamation in Galveston, thus belatedly bringing about the freeing of 250,000 slaves in Texas. The tidings of freedom reached slaves gradually as individual plantation owners read the proclamation to their bondsmen over the months following the end of the war. The news elicited an array of personal celebrations, some of which have been described in The Slave Narratives of Texas (1974). The first broader celebrations of Juneteenth were used as political rallies and to teach freed African-Americans about their voting rights. Within a short time, however, Juneteenth was marked by festivities throughout the state, some of which were organized by official Juneteenth committees."