National Connecticut Day is observed every August 10, recognizing Connecticut as the fifth of the Thirteen Colonies to ratify the U.S. Constitution and join the Union. Established by National Day Calendar as part of its National State Days project, the holiday celebrates Connecticut's rich history and culture. The state, named after the Connecticut River, has a significant historical background, including the establishment of early English settlements such as the Saybrook Colony and the Connecticut Colony in the 1630s. Connecticut played a vital role during the American Revolution by supplying troops and materials, even though no major battles occurred within its borders. The state ratified the U.S. Constitution on January 9, 1788, with an almost unanimous vote, further solidifying its importance in American history. National Connecticut Day highlights these historical milestones, fostering appreciation for the state's contributions to the nation.