Friday, Sept. 15 marks the first day of a month-long celebration of Latino American citizens, their cultures and contributions known as National Hispanic Heritage Month.

On Wednesday, President Donald Trump signed the observation's annual proclamation, which highlighted Hispanic Americans as a "testament to the American promise that anyone can succeed in the United States through hard work."

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Here are five things to know about Hispanic Heritage Month:

What is National Hispanic Heritage Month?

According to the official website, the  month-long celebration of the country's 57 million Latino-American citizens "pays tribute to the generations of Hispanic Americans who have positively influenced and enriched our nation and society."

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Which countries or regions are celebrated?

Hispanic American citizens have ancestors from Spain, Mexico, the Caribbean and countries in Central and South America.

When did National Hispanic Heritage Month begin?

The observation of National Hispanic Heritage Month was enacted into law on August 17, 1988, on the approval of Public Law 100-402.  This was an amendment to Pub. L. 90-498 (seen here), which authorized and requested the President to proclaim the week including Sept. 15 and Sept. 16 as National Hispanic Heritage Week.

Credit: Library of Congress

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Credit: Library of Congress

It all began in 1968 under President Lyndon Johnson. Congress passed Public Law 90-498, which authorized and requested the President to issue an official annual proclamation of Hispanic Heritage Week.

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Congress later passed Public Law 100-402, which amended the previous law to establish a month-long celebration, on Aug. 17, 1988.

Source: Library of Congress

Why Sept. 15?

According to the official website, Sept. 15 is the anniversary of independence for multiple Latin American countries, such as Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua.

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Several other days during the month are notable as well, including Mexico’s and Chile’s independence days (Sept. 16 and Sept. 18, respectively) as well as Columbus Day on Oct. 12.

What do people do during National Hispanic Heritage Month?

There are festivals, special museum exhibits, cultural events and more all over the country to commemorate National Hispanic Heritage Month.

Some featured exhibits:

More information at hispanicheritagemonth.gov.