Kai Winn Adami of Star Trek Deep Space 9.

In the Star Trek fictional universe, the Bajoran Kai was the supreme religious leader of the Bajoran faith.

The Kai would be roughly similar in rank to the Pope of the Roman Catholic Church on Earth. However, unlike the Pope this individual could be either male or female, could be married, and could even have children. Unlike the election of the Pope - which is held among the high ranking Cardinals - it appears that the Kai is chosen in an election held by the entire Bajoran people, though typically candidates come from the Vedek assembly of high-ranking clerics.

When Starfleet forces initially arrived at Deep Space Nine, the Kai was a woman named Opaka. She introduced Commander Sisko to an Orb of the Prophets. Later Opaka had to be left behind on a prison planet when she had been infected by nano-machines on the planet.

Afterwards, the position of Kai was vacant for about a year. During this time, two leading candidates for the office emerged. One was Vedek Winn Adami - a member of a small conservative order on Bajor who harbored anti-Federation feelings. The other was Vedek Bareil Antos, a kindly man who had a relationship with Major Kira of DS9.

Vedek Bareil withdrew his name from consideration to save the memory of Kai Opaka from embarrassment following the discovery of information that she had collaborated with the Cardassians to save the lives of thousands of Bajorans. As a result, Vedek Winn won the election and became the next Kai.

Bareil became a trusted advisor to Kai Winn. The Kai changed her mind and adopted a more friendly stance towards the Federation and Commander Sisko. Bareil eventually began peace talks with the Cardassians. He later died in an accident. At the time of his death he assisted the Kai to conclude the peace agreement.

Kai Winn later tried to consolidate her hold on power after the death of the Bajoran First Minister. Her actions nearly caused a civil war. Major Kira of DS9 convinced her old friend and resistance cell leader Shakaar to run for election to the post to head off a civil war. Shakaar was able to handily win election to the post of First Minister, after Kai Winn withdrew from the election.

Later, at the beginning of the Dominion War, Captain Sisko convinced Kai Winn to sign a non-aggression treaty with the Dominion. Sisko felt the time was not right for Bajor to choose sides in the war - if they did they would be destroyed.

When the Prophets wanted to conduct their battle against the Pah Wraiths on the station, Kai Winn interfered with their battle. This resulted in a stalemate between the Prophets and Pah Wraiths. Major Kira then told Winn that Sisko - an outsider and infidel - had more faith than she did.

With the end of the Dominion War in sight, Kai Winn was tempted to join with Dukat - who had been surgically altered to appear as a Bajoran - in worship with the Pah Wraiths. Kira advised Winn that she could be redeemed if she stepped down from the post, however Winn refused.

Kai Winn turned away from the prophets, and became a tool of the Pai-Wraiths. She helped Dukat to the Fire Caves - the home of the Pah Wraiths. She betrayed Dukat by giving him poison. However Dukat was able to recover from the poison with the assistance of the Pah Wraiths. Captain Sisko arrived and defeated Dukat and the Pah Wraiths. Kai Winn was consumed and killed by the Pah Wraiths.

At the end of the Deep Space Nine television series, the post of Kai was again vacant. However an election for the next Kai was underway at the time. It has not been revealed who won that election.