Rev. James B. Thomas is a significant figure in the history of Juneteenth, as he played a key role in its establishment as an official holiday in Texas.

Juneteenth, also known as Emancipation Day or Freedom Day, commemorates June 19, 1865, when Union General Gordon Granger arrived in Galveston, Texas, and announced the emancipation of enslaved African Americans in the state. This announcement came two and a half years after the Emancipation Proclamation had been issued.

Rev. James B. Thomas was an African American minister and community leader in Galveston at the time. He was instrumental in organizing the first public celebration of Juneteenth in 1866, the year following General Granger's announcement. Rev. Thomas worked alongside other community leaders to plan and coordinate the event, which included religious services, speeches, prayer, and festivities.

Rev. Thomas continued to be actively involved in the Juneteenth celebrations in Galveston for many years. He served as a community advocate and played a vital role in preserving the significance and traditions of the holiday. His efforts helped ensure that Juneteenth remained a cherished occasion for generations to come.

Thanks to the efforts of Rev. James B. Thomas and others, Juneteenth gradually gained recognition and spread beyond Galveston. It became an important holiday commemorated across Texas and eventually throughout the United States. In 1980, Juneteenth was officially recognized as a state holiday in Texas, and in 2021, it gained national recognition with the passage of the Juneteenth National Independence Day Act.