NAIROBI — A data analytics firm at the center of a controversy over its acquisition and use of personal Facebook data in the 2016 United States presidential election is under new scrutiny for its role in Kenya’s presidential election last year.

Senior officials of Cambridge Analytica, whose parent company is the SCL Group, said in an undercover video by Channel 4 News of Britain that the company played a critical role in President Uhuru Kenyatta’s two campaigns, in 2013 and 2017.

The revelations come only weeks after Mr. Kenyatta and his chief rival, Raila Odinga, reconciled after months of contention.

In the video, Mark Turnbull, a Cambridge executive, said the company twice rebranded Mr. Kenyatta’s political party, wrote his campaign speeches and his political platform, and twice conducted surveys of 50,000 people to ascertain Kenyan voters’ hope and fears.

A spokesman for Mr. Kenyatta referred inquiries to his party, the Jubilee Party, whose top official did not respond to messages seeking comment on Tuesday night.

Mr. Kenyatta won re-election last October after two presidential votes. The first, in August, was nullified by the Supreme Court, which cited widespread irregularities and ordered a second election. Mr. Odinga pulled out of the second vote, which was held in October, saying the process was unfair.

The acriminous political season included divisive speech by both parties, observers said, and continued well past Mr. Kenyatta’s inauguration. The two archrivals shook hands and reconciled this month.

Moses Karanja, a researcher on a project at Strathmore Law School in Nairobi about social media and misinformation during the presidential election, said the recent reports about Cambridge’s role in Kenya, and its abuse of Facebook data globally, reinforced concerns raised in his own work about how Kenyans’ personal data was accessed by political parties and even by government institutions, like the elections commission.

He said targeted text messages that he and others received during the campaign season suggested that individuals’ voter registration information, social media data and telephone numbers were being independently linked — although it’s still unclear how.

“We don’t know how they accessed this data, or how it all ended up being linked to phone numbers and such,” Mr. Karanja said. “For me that’s scary. Those are questions those platforms should answer.”

Gacheke Gachihi, who leads the Mathare Social Justice Center in Nairobi, said Cambridge’s branding for Mr. Kenyatta was “divisive propaganda,” raising ethnic enmity.

“The way you paint your opponent, you paint also his supporters,” he said, “and you and your ethnic base will feel like, ‘This man is a devil.’ That undermines the work we are trying to do for social justice.”

Local news media had reported last spring that Mr. Kenyatta’s party had retained Cambridge for his re-election campaign. And David Murathe, the vice chairman of the Jubilee Party, told Reuters on Tuesday that SCL helped the campaign with branding last year.

Mr. Odinga’s party also enlisted a data-driven political consulting firm, but its on-the-ground team was deported from Kenya just a week before the election, according to The Los Angeles Times.

On its website, Cambridge names Kenya as one of its political case studies, describing a 47,000-person survey it conducted in 2013 to identify Kenyan voters “real needs (jobs)” and “fears (tribal violence),” as well as their “preferred information channels.”

The company also said it targeted youth voters with a social media campaign.

Cambridge’s parent group, SCL, described similar activities on an archived page of its website, and said it also advised on communications, branding and strategy during the electoral period.

Cambridge said its survey was “the largest political research project ever conducted in East Africa.” Mr. Turnbull told Channel 4’s undercover reporter that it repeated the survey in 2017.

Those survey results, Mr. Karanja said, could reverberate beyond social media campaigns and “be translated into non-Internet platforms like radio, television advertisements and billboards.”

He said his research team documented several examples of misinformation spreading on WhatsApp and other social media channels and filtering down to local talk radio shows or newspaper articles.