The first flurry of diplomats decamped from Kyiv in mid-February, well before shells began slamming into and around the historic city. The next wave of embassies packed up and left Ukraine’s capital a few weeks later, when the war began in earnest, moving their operations west and away from the fighting.

Through it all, the Vatican’s diplomatic mission stayed put.

In recent weeks, with Russian troops in broad retreat from the region, dozens of embassies have reopened in the city or announced plans to return. The United States said this week it would reopens its embassy.

Archbishop Visvaldas Kulbokas, the Holy See’s ambassador to Ukraine, said that as long as there was a city standing, he would stay. Without the consular workload of a typical embassy or the political or economic interests of a secular state, the considerations were different for the nunciature, as the Vatican’s diplomatic mission is known.

“Bishops and priests, they stay with the people. I stay with the people because it’s part of my identity,” he said in a phone interview.

For weeks, Archbishop Kulbokas and his staff of five — down from the embassy’s normal staffing of 11 — worked, ate, prayed and slept in a couple of rooms on the ground floor of the nunciature, a yellow-walled five-story building in the tree-lined Shevchenkivskyi district of Kyiv. His days have been filled fielding calls to coordinate humanitarian assistance, requests for help from within the country and offers of aid from Catholic organizations abroad, he said.

On Thursday night, he and his staff heard the now familiar whoosh of incoming missiles, and the ensuing blasts about a kilometer away. It was at least the third time explosions had come within earshot of the embassy.

Faced with the overwhelming need for help, the archbishop said he hasn’t had time to give too much thought to the risks of staying. He spent the first weeks of the war trying to help evacuate children and staff members from orphanages near the front lines in the east. In the latter half of March he sought, unsuccessfully, to get relief to the besieged city of Mariupol.

Russian soldiers denied the church access to the city, turning down his requests to provide humanitarian aid jointly with an Orthodox bishop, he said. Almost half the population in Ukraine is Eastern Orthodox; Roman Catholics make up a small fraction of believers in the country.

Archbishop Kulbokas, a Lithuanian, was dispatched to Kyiv only last fall after working on Ukraine-Russia relations at the Vatican’s Secretariat of State. He also served in the Holy See’s embassy to Russia, where he translated in meetings between Pope Francis and President Vladimir V. Putin of Russia.

In mid-April, he left Kyiv to accompany Cardinal Konrad Krajewski on visits to nearby suburban towns including Bucha and Borodianka, where mass graves were being excavated in the wake of the withdrawal of Russian troops. Now, seeing the written names of the towns brings tears to his eyes, the archbishop said.

“In every religion, human life is the priority,” he said. “If we really believe in God, our priority would be that of helping each other.”