In the Kazakh capital Nur-Sultan, which was called Astana until 2019, the so-called Congress of Leaders of World and Traditional Religions is taking place for the seventh time.
Francis is the first pontiff to attend the international meeting organised by the Kazakh government.
Kazakh President Kassym-Jomart Tokayev deemed his presence an honour.
Until now, John Paul II had been the only Pope to visit post-independence Kazakhstan, in 2001.
For the 85-year-old Pope, who suffers from knee problems and spends most of his time in a wheelchair, it is his third trip abroad in 2022, following trips to Malta and Canada.
The Pope described his trip as a "pilgrimage of dialogue and peace" as he addressed the faithful on Sunday.
The head of the Catholic Church landed in Nur-Sultan and was received by President Tokayev.
Following the airport welcome, Francis attended a reception with the president and diplomats.
Upon his arrival, Francis stressed that his trip is in solidarity with all those seeking peace in the world.
Calling himself a "pilgrim of peace," Francis said he wishes to amplify the cries of those who advocate for peace around the world.
He addressed the war in Ukraine while at the reception, calling the Russian invasion tragic and senseless.
Speaking of such conflicts threatening the globe, the Pope said the world must find harmony.
Once again, the Pope reaffirmed that Russia is responsible for the war in Ukraine.
Francis was previously criticised for not doing so when the Russian invasion began.
The Pope traditionally sends greetings to the capitals of the countries he flies over, however his outbound flight from Rome to Nur-Sultan avoided Russian airspace, sparing him a Telegram message to President Vladimir Putin.
The Congress of Leaders of World and Traditional Religions starts on Wednesday.
About 100 delegations from 50 countries are due to attend the two-day meeting.
On the first day of the congress, Wednesday, a joint prayer and bilateral meetings are on the agenda.
Francis also plans to celebrate a Mass.
On Thursday, a final statement by the religious leaders is to be read, then his return flight is scheduled.
A meeting with Russian Orthodox Patriarch Kirill of Moscow, which the Vatican had hoped for, will not take place.
The Russian religious leader, who has always defended the war launched by President Vladimir Putin in Ukraine, recently bowed out from travelling to Nur-Sultan.
Kazakhstan, with a population of 19 million, is home to a small community of about 125,000 Catholics.
About 70 per cent of Kazakhs are Muslim while 26 per cent are Orthodox Christians.
Pope Francis has praised the coexistence of the different religious groups there.
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