DODOMA, Tanzania — Shortly before midnight on a spring night last year, Samia Suluhu Hassan, then Tanzania’s first female vice president, appeared on television to announce to a shocked nation that the president was dead.

President John Magufuli, an autocrat known as “The Bulldozer,” had denied that coronavirus existed in his country, rejected Covid vaccines and died after a weekslong absence from public view amid unconfirmed reports that he had contracted the virus.

His death catapulted Ms. Hassan to a historic position as Tanzania’s first female president. Known as “Mama Samia,” she is currently the only female head of government in Africa. On Friday, she is set to meet in Washington with a fellow path-breaker, Kamala Harris, the first woman and first woman of color to be vice president of the United States.

Since taking office, Ms. Hassan has set off on a different path than her predecessor: She encouraged Covid vaccinations by publicly taking the shot herself, lifted a ban on pregnant girls in schools and began to amend some Magufuli-era economic regulations to lure back investors.

But her first challenge, Ms. Hassan said in an interview last week at the state house in the capital, Dodoma, was to overcome the notion that a woman could not lead Tanzania.

“Most of the people couldn’t believe that we can have a woman president and she can deliver,” Ms. Hassan said. “The challenge was to create a trust to the people that yes, I can do it.”

She said that other African female leaders — including Liberia’s first female president, Ellen Johnson Sirleaf, and Sahle-Work Zewde, the president (though not head of government) of Ethiopia — quickly came to her support, urging her in a virtual meeting to remain confident, seek counsel and listen to her inner voice.

“They all gave me courage that you can do it,” said Ms. Hassan, who was fasting for the Muslim holy month of Ramadan.

Since ascending to power in March last year, Ms. Hassan has positioned herself as a unifying national figure willing to challenge the establishment and bent on bringing her country in from the cold after five years of isolationism under Mr. Magufuli, who rarely traveled abroad.

Tanzania, a nation of 60 million people that borders eight other countries in eastern, central and southern Africa, was long seen as a bulwark of stability in a region torn by ethnic strife and civil war.

But Ms. Hassan, who is expected to run for president in 2025, takes the helm of a polarized nation with a battered economy and growing unemployment, a slow pace of vaccine deployment and a growing clamor for constitutional overhauls.

In addition to meeting American officials during her trip to the United States, she is also set to court investors and promote Tanzania as a vibrant tourist destination.

In Washington, one issue that Ms. Hassan is likely to face is the war in Ukraine. Tanzania was among the African nations that abstained from the United Nations vote condemning the war — a move Ms. Hassan said was in line with Tanzania’s longstanding position of nonalignment.

Pushed on this, she said that in “Tanzania, we don’t know why they are fighting,” adding that Russia and Ukraine should sit down to talk. “The world has to convince Putin not to fight,” she said.

Ms. Hassan, 62, was born in the Zanzibar archipelago off the coast of mainland Tanzania to a stay-at-home mother and schoolteacher father. After high school, she completed bachelor’s and postgraduate degrees in economics and public administration in schools in Tanzania and Britain. She later worked with the World Food Program and held positions in various nongovernmental organizations in Zanzibar.

But at the turn of the century, she decided to try her hand in government.

A member of the ruling Chama Cha Mapinduzi party — or Party of the Revolution — since the late 1980s, she was elected as a lawmaker in Zanzibar in 2000 before joining the national Parliament in 2010. Ms. Hassan, who sits in the party’s central committee, quickly went up the ranks, becoming a minister in the vice president’s office and then rising to the vice presidency in 2015. Ms. Hassan is married to Hafidh Ameir Hafidh, a former agriculture lecturer, with whom she has three sons and one daughter.

Ms. Hassan, who is soft-spoken and comes across as reserved, said that as vice president, it was “tough” working with Mr. Magufuli at times, and that she argued with him on several issues, including his Covid denialism. She rebutted the idea that he had succumbed to Covid and said he had died of heart complications.

As president, she said, her main priority was to revive the economy, build thousands of schools and health clinics, extend clean water and electricity to rural areas and complete key infrastructure projects — including a railway line and a major hydropower plant. She said that more than 250 new businesses had already been registered in the country last year.

Yet concerns have persisted about the pace of change under her government.

Over the past year, activists were abducted, two newspapers were temporarily suspended by the government and the main opposition leader, Freeman Mbowe, was jailed for several months on terrorism-related charges before his release. Political rallies outside elections have been banned in the country since 2016, when the government accused the opposition of wanting to use them to cause mass civil disobedience. Activists also questioned whether Ms. Hassan was committed to reviewing the constitution, which grants vast powers to the executive and was adopted in 1977, when the country was still a one-party state.

Ms. Hassan said she wanted to focus on fixing the economy before turning to the “huge” and “costly” endeavor of changing the constitution. She said she created a task force from within the political parties council to make recommendations on changes, including lifting the ban on political rallies. She added that she was intent on leveling the playing field, even if it cost her the presidency in the next elections.

She has also struck a conciliatory note with the political opposition and civil society.

On a recent morning, she arrived at a packed hall in the capital to preside over a conference discussing how to improve the democratic space in the country. Sitting by her side onstage was one of the leaders of the country’s main opposition parties, who under her predecessor had been arrested and found guilty of sedition, and whose fellow party members were beaten, tear-gassed and denied the chance to hold rallies.

“Things have changed,” Zitto Kabwe, the opposition leader, said in an interview the next day. “We started to breathe some fresh air from the day the new president took office.”

But while he would like to see the political changes put in place quickly, Mr. Kabwe said he also understood Ms. Hassan’s predilection for incremental change. “She’s a leader who wants consensus, and consensus takes time,” he said.

Last year, Ms. Hassan’s government lifted bans on four newspapers, but she has yet to change some of the restrictive laws that have been used to undermine media freedom.

Simon Mkina, the publisher and editor in chief of Mawio, a weekly investigative newspaper that she reinstated, said she should overhaul media laws so that future leaders do not abuse them. “She must take action,” he said.

With three more years before the next election, Ms. Hassan has her work cut out for her.

Fatma Karume, a prominent Tanzanian lawyer who was disbarred and had her office bombed for challenging Mr. Magufuli’s government, said Ms. Hassan has the chance to restore Tanzanians’ faith in democracy and transform the country.

“She could leave behind a legacy that few other presidents have managed,” Ms. Karume said in an interview at her home in the port city of Dar es Salaam. “And imagine doing that as a result of a historical accident. It will be amazing.”