BRASÍLIA — Jair Bolsonaro, the former right-wing president of Brazil, returned home on Thursday morning after a three-month self-imposed exile in the United States following his defeat last year in an election that tested the stability of one of the world’s biggest democracies.

He returns to a series of investigations that could see him arrested and face prison if found guilty for his role in spreading baseless claims that Brazil’s election system was vulnerable to fraud — despite reviews by independent security experts showing otherwise — and that the left was bent on stealing the vote.

In January, Brazil’s Supreme Court said it would investigate Mr. Bolsonaro for inspiring the far-right mob that invaded and ransacked the country’s Congress, Supreme Court and presidential offices on Jan. 8, underscoring that the former leader could soon face legal consequences for an extremist movement he helped build.

Mr. Bolsonaro is the subject of five other Supreme Court inquiries, including for his handling of the pandemic; accusations of spreading misinformation; and a leak of classified information when he discussed a hack of the country’s election agency to support his claims that Brazil’s voting system is unsafe.

He also faces over a dozen investigations by the country’s electoral body and if convicted in any of those cases he would be ineligible for office for eight years.

The political climate in Brazil has been tense since Mr. Bolsonaro’s departure, with many of his allies calling for his return. For his part, Mr. Bolsonaro, has been critical of the current leftist administration of President Luiz Inácio Lula da Silva.

During his time in the United States, which he largely spent in Florida, Mr. Bolsonaro met with conservative activists and pundits, appearing at various events, from the Conservative Political Action Conference to the opening of a burger restaurant.

At the airport in Brasília on Thursday morning, dozens of supporters gathered at the arrivals gate to greet Mr. Bolsonaro, though he was prevented from meeting with them. Federal Police officials ordered the former president and his staff to use a separate exit for security reasons.

The former leader’s motorcade then took him to his Liberal Party headquarters, where he met with high-ranking right-wing politicians, family members and some of his staunchest allies.

Mr. Bolsonaro has yet to speak publicly since his return.

Outside the business center that hosts his party’s headquarters, a few dozen supporters gathered hoping to hear from the former president.