Monday was the first time Juneteenth was celebrated as a federal holiday.
The actual holiday was on Sunday but was observed on June 20 with a huge celebration in Suffolk.
The Juneteenth Jubilee took place at the H. Lee Dennison Building in Hauppauge from 11 a.m. to 1 p.m.
The jubilee celebration featured remarks by Attorney General Letitia James and a keynote presentation by Bishop Andy C. Lewter.
Juneteenth honors the end of slavery in the United States and is considered the longest running African American holiday.
Jason Richberg, minority leader of the state Legislature, says the celebration is honoring the history of the holiday.
"Suffolk County is a melting pot," Richberg says. "It's important that we acknowledge all our histories, not just some. That's what Juneteenth is about. It's about spreading the birth of freedom to everyone."
The event also included musical performances by Elder Jeff Roberson and the NULIFE signers.
The event featured two food trucks offering African American cuisine.
Some residents say they brought their children out to teach them the significance of the day.
"I need my children to know their history, their culture and it's all a learning experience," says Christina Wellington. "I need them to soak it all in. That's why we're here."
Texas the first state to recognize Juneteenth as a state holiday in 1980.
This year marks the 157th anniversary of Juneteenth.