The Arlington County School Board named its first Latino board leader on Monday — a vote that quelled a simmering community debate — and extended the contract of the school system’s superintendent.

The twin votes cemented the leadership team for the fast-growing system, with Emma Violand-Sanchez as school board chairwoman for the next year and Superintendent Patrick K. Murphy on board for another four years.

The board voted unanimously to extend Murphy’s tenure, assuring that he will remain at the helm as the system carries out a long-term capital improvement plan to make room for a student population that topped 22,000 this year.

Murphy will earn an annual salary of $209,976, which includes a 5 percent increase that he is required — under a law passed in Richmond this year — to contribute to the state retirement system.

He became chief of Arlington’s schools in 2009 and has faced a series of difficult budgets, the departures of several senior administrators and allegations of harassment made by a respected middle-school principal who resigned mid-year in 2011.

But also under his leadership, the school system has maintained its generally high performance and has by some measures narrowed the stubborn achievement gap among subgroups of students.

“Much work is ahead of us, but we have a very strong base on which to build,” said Violand-Sanchez, who served as the board’s vice chairwoman until her election as chairwoman Monday.

The vice chair often rotates into the chairmanship, but in recent weeks, outgoing chairwoman Abby Raphael had reportedly expressed interest in retaining the position for another year.

That prompted letters of protest from community activists, including the Arlington Latino Network, whose members said failing to elevate Violand-Sanchez into the chairmanship would “send a message to the the school community that runs counter to the board’s stated commitment to racial and ethnic equality.”

The African American Parents Network also wrote to the board expressing concern.

Raphael surprised advocates and did not ask Monday to be considered for the chairmanship. Instead, she seconded the motion to elect Violand-Sanchez. It passed with four votes and one abstention.

Raphael handed the gavel to Violand-Sanchez, and the two embraced on the dais.

“I regret that this discussion took on ethnic and racial overtones that caused discomfort,” said Violand-Sanchez, a Bolivian-born educator who oversaw the school system’s English-as-a-second-language programs before retiring in 2007. “This has been difficult for all of us, but it has also provided us an opportunity to demonstrate that we can bridge our differences.”

Her election was greeted with applause from more than two dozen people in the audience, several of whom spoke in her support.

“The defining element of Arlington school board’s leadership is the rich diversity of perspectives, experience and expertise that you each bring to the board,” said Gabriela Uro, a parent who spoke to the board Monday on behalf of the Arlington Latino Network. “Your decision today acknowledges this very diversity.”

Latino children are Arlington’s largest minority group and account for about 28 percent of the student population.

The sole abstention belonged to Sally Baird, who said she supported Violand-Sanchez but wanted to register an objection to the idea that the board’s leadership rotation is — or should be — automatic. She said she was disappointed that the board’s internal discussions about the future had leaked to the public.

“Ultimately, this board needs to make its leadership decision each year,” said Baird.

Baird, elected vice chairwoman Monday, said whether she leads the board in the future should depend on whether she earns her colleagues’ respect and trust. School officials said there were several instances in the past two decades when the vice chairman did not become chairman.