Lars Olof Jonathan Söderblom (Swedish pronunciation: [ˈnɑːtan ˈsøːdɛrblʊm]) (15 January 1866 – 12 July 1931) was a Swedish clergyman. He was the Church of Sweden Archbishop of Uppsala between 1914 and 1931, and recipient of the 1930 Nobel Peace Prize. He is commemorated in the Calendar of Saints of the Lutheran Church and in the liturgical calendar of the Episcopal Church (USA) on July 12.

Söderblom was born in a village called Trönö, today Söderhamn Municipality, Gävleborg County. His father was a priest and a devoted Christian with a strong personal faith.

He enrolled at Uppsala University in 1883. Although not initially convinced what he wanted to study, he eventually decided to follow in his father's footsteps. On returning from a journey to the U.S., he was ordained priest in 1893.

During the years 1892 and 1893, Söderblom was first vice president and the president of the Uppsala Student Union.

In 1912, he became a professor of Religious studies at Leipzig University. But already in 1914, he was elected as Archbishop of Uppsala, the head of the Lutheran church in Sweden. During the First World War, he called on all Christian leaders to work for peace and justice.

He believed that church unity had the specific purpose of presenting the gospel to the world and that the messages of Jesus were relevant to social life. His leadership of the Christian "Life and Work" movement in the 1920s has led him to be recognised as one of the principal founders of the ecumenical movement. His was instrumental in chairing the World Conference of Life and Work in Stockholm, in 1925. He was a close friend of the English ecumenist George Bell.

He was the pastor at the church that Alfred Nobel went to and in 1930 was one of the recipients of the Nobel Prize.

After his death in Uppsala, Sweden, in 1931 his body was interred in Uppsala Cathedral.