Filmmaker Gilberto Gonzalez has fond memories of growing up in the 1970s in the Puerto Rican enclave of Spring Garden. On weekends - when he woke up in the morning or fell asleep at night - he listened to men in the nearby park singing and drumming songs from their island home.

But those also were tough times in Philadelphia's original barrio, darkened by violence with non-Puerto Ricans and ongoing tension with law enforcement. And it's the reason the 20Gs came to be the protectors of the neighborhood.

For more than 50 years, members of this gang made sure mothers weren't hassled walking back from markets, that fathers found their homes safely after late nights socializing, that children were unharmed traveling to and from school.

"They were my role models growing up," said Gonzalez, 51. "They defended us. They protected us. They fought, but they fought for us."

In the documentary Cuentos: The 20Gs, Gonzalez tells the little-known story of the informal, intergenerational group, which at its height in the 1970s had more than 200 members.

In February, Gonzalez shared parts of his documentary - three years and $12,500 in the making - with a crowd of former neighborhood residents and some of the 30 living members of 20G at West Philadelphia's Scribe Video Center.

Because Gonzalez plans to send the documentary to various film festivals, he was unable to show the complete work. He plans to arrange public viewings in Philadelphia this fall, including one at City Hall with the help of City Councilwoman Maria Quiñones-Sánchez, whose office gave $1,000 to the filmmaker.

Watching their stories told at the first showing, the former street fighters teared up.

"No one knew about their struggles with the white community, the African American community, the police," said Gonzalez, a senior graphic designer at Community College of Philadelphia. "They've felt like they never had a voice. Now they have a voice in this film."

This is Gonzalez's second documentary about the neighborhood. The first, released in 2012, looked at gentrification in Spring Garden. He wanted to tell the story of the 20Gs because it was close to his heart - one of his babysitters was a member.

Gonzalez - listed among other roles as director, producer, and editor - self-funded most of the work. His efforts were bolstered by the grant from Quinones-Sanchez's office and more than $3,000 donated by 20Gs. The 20Gs also have performed traditional music at film fund-raisers.

Although gangs usually have a negative connotation, Orlando "Sunshine" Cruz, now 56, who became a member of 20Gs like his older brother, noted the group didn't exist for personal gain or profit. Drugs and guns weren't prevalent before the 1980s. Named for the corner of 20th and Green Streets and pronounced "two-oh-jeez," this gang's mission was singular.

"We were close-knit," said Efraim "Gaucho" Feliciano, 58, who joined at 14, following in the footsteps of his deceased father. "If something happened to one person, we all felt the pain."

Puerto Ricans began heavily populating the Spring Garden neighborhood - an area roughly bounded by 22nd and Broad Streets, and Fairmount and Spring Garden Streets - about 100 years ago, when labor recruiters in Philadelphia focused on attracting them because they were already citizens (Puerto Rico is a U.S. territory). Clemente Park and Playground, on the 1800 block of Wallace Street, was their playground. Their church was just beyond the borders, at 19th and Spring Garden Streets: La Milagros - officially Capilla Catolica Hispana de la Medalla Milagrosa, or Our Lady of the Miraculous Medal - opened in 1912 and was the first in the city to offer Spanish-language Mass.

With the new residents came new tensions. Other gangs sprang up as a way to protect the neighborhood - La Pachanga, the Little Rascals - and, by the 1930s, the 20Gs had formed. It lasted until the '80s, when gentrification pushed many Puerto Ricans and their families farther north and into the suburbs.

Gonzalez, who lived on the 1700 block of Green Street until his family moved to Kensington in the early 1980s, remembers "police swinging nightsticks and making people bleed and then sending them home."

"That was the pattern in the neighborhood," Gonzalez said. "People would get picked up, get charged with whatever, and do time."

Yolanda Rivera of Bucks County lived on the 1800 block of Green Street before leaving to go to college. She remembers being beaten up at school because she didn't speak English - she didn't even know why she was targeted until another Puerto Rican girl translated for her.

"We couldn't go over to the other side of Fairmount," Rivera said. "You knew if you walked over there, even to go to the store, you were taking a big chance."

Although these transplants were American citizens, many neighbors did not see them that way. Two violent incidents mentioned in the documentary - one in July 1953, one in June 1973 - continued the necessity for the 20Gs:

In 1953, a fight in a Spring Garden bar spilled outside and grew to include an estimated 300 residents and 75 police officers in a two-hour conflict between Puerto Ricans and "whites" that spread across two city blocks. Seven people were severely injured; more than a dozen were arrested.

In 1973, police arrested six residents of Puerto Rican descent after an 18-year-old was killed and his girlfriend raped outside the Art Museum. One of the men arrested testified against the other five, and they went to jail to serve lengthy sentences.

Eventually, one man was able to prove he hadn't been in the city at the time of the crime. Another served nine years before it was revealed evidence was withheld that could have helped his case. He was acquitted in a second trial.

The 20Gs who attended the film showing wonder how many current Spring Garden residents know these stories.

That's one reason a documentary like this is so important, said historian Victor Vazquez-Hernandez, who appears in the film. Now a professor and chair of the social sciences department at Miami Dade College, Vazquez-Hernandez lived in Philadelphia for 20 years, working as an administrator and instructor at Temple University, where he earned his doctorate in history. The course he created about Puerto Ricans in Philadelphia still is taught there.

"That which is not documented does not exist," Vazquez-Hernandez said. "There's a richness to this history that is often overlooked. It's important to remember the contributions this community has made to the mosaic of Philadelphia."

The remaining 20Gs still make music at Clemente Park and Playground, but now it's once a year at a neighborhood reunion. When Cruz went by himself to the park one day to reminisce, police pulled up to ask him why he was there. Gonzalez, too, has felt unwelcome near his former home.

"When I walk around there, I look at where I used to live and take pictures, and I get funny looks from people," he said. "It definitely brings up a lot of emotions."