After graduating from Brooklyn Technical High School, she was accepted into and enrolled in Spelman College in Atlanta, Georgia in 1997, inspired by the actions of characters on The Cosby Show and A Different World.

[4] Based on her 1999 NYU graduate work[5] and a trip to Bilbao, Spain, Cumbo founded[4][6] and served as the executive director of the Museum of Contemporary African Diaspora Arts (MoCADA).

"[8] Originally based in a building operated by the Bridge Street AME church in the Bedford-Stuyvesant section of Brooklyn,[1] the institution moved to its current location in the borough's gentrified Fort Greene section within the BAM Cultural District with the help of the Brooklyn Academy of Music's Local Development Corporation, which included Bruce Ratner, the Barclays Center and Atlantic Yards developer, on its board.

[6][9] In 2012, the museum landed a $100,000 grant from the Rockefeller Foundation to pay for a two-year program that brought monthly concerts to public spaces in nearby NYCHA Houses like Walt Whitman, Ingersoll, and Farragut in Fort Greene that drew crowds up to 500 or 600.

[4] In December 2013, one month before she was sworn in, a series of attacks took place targeting Jewish residents of Crown Heights, Brooklyn, totaling at least eight victims including children.

"[33] Elected in 2013 in a crowded Democratic primary race, Cumbo, unchallenged by a Republican candidate,[citation needed] succeeded Letitia James.

[31][37] Despite this, she won the council seat[37] on a platform, in part, of expanding and developing arts and cultural tourism in the district and making improved use of public spaces including parks.

In May 2014, she was fined $7,868 by the New York City Campaign Finance Board for taking contributions above the limit from a group pushing for a ban on the horse-carriage industry.

On October 15, 2014, Cumbo joined by Speaker Melissa Mark-Viverito, Rosemonde Pierre-Louis, commissioner for the Mayor's Office to Combat Domestic Violence and other citywide elected officials, posted at subway stations across the city in a campaign that Cumbo organized in order to raise awareness of the problem of domestic violence in honor of "NYC Go Purple Visibility Day".

During Jumaane Williams's campaign for New York City Public Advocate, The Daily News broke the story of his 2009 arrest in a domestic dispute, the records that had been sealed, which were used by competing candidates.

[51] Cumbo, who went to high school with Williams, wrote a letter demanding to know if the law enforcement sources of the story broke city policy in doing so.

[53] Cumbo made local headlines again in late March 2015 when she asked why there were "blocs" (possibly "blocks"[54]) of Asians living in two Fort Greene housing projects.

"[54][55] Queens Congresswoman Grace Meng, another Asian-American New York City representative, denounced Cumbo's idea, saying that it was "thinly disguised segregation based on race, color, creed or national origin.

"[57] In 2016, Cumbo was in favor of proceeding with the development of the Bedford Union Armory with BFC Partners via a lengthy public review process, despite community opposition, saying "Let's just continue to negotiate, see what the final outcome is, and if it's satisfactory," claiming adjustments could be made along the way.

[59] The new plan passed six months later and still attracted protesters with Jonathan Westin of Communities for Change saying "The entire process was fixed from the beginning so the Mayor could push through a deal to one of his favored developers....