National Hispanic Heritage Month celebrates Hispanic and Latino history and culture and the contributions of Hispanic Americans. The event began in 1968 when Congress deemed the week, including September 15 and 16, National Hispanic Heritage Week to celebrate the contributions and achievements of the diverse cultures within the Hispanic community. The dates commemorate two key historic events: Independence Day, honoring the formal signing of the Act of Independence for Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua (September 15, 1821), and Mexico's Independence Day (September 16, 1810). In 1988, the observation was expanded to a month-long period, to include El Dia de la Raza on October 12, celebrating the influences of the people who came after Christopher Columbus and the multicultural, multiethnic society that evolved as a result. Today, the Latino population in the U.S. exceeds 60 million and constitutes 19% of the total population. Each year a different theme for the month is selected and a poster is created to reflect that theme.

Source: Smithsonian Institution