Quakers, or Friends, are members of the Religious Society of Friends, or Friends' Church—an international family of diverse Christian religious organizations that focus on the priesthood of all believers. Quakers today are theologically diverse: mostly regarded as Christian, they include those with evangelical, holiness, liberal and traditional Quaker understandings of Christianity. From the end of the 20th century, small but vocal groups of Friends with Christian atheist or universalist beliefs have emerged.

Quakers are organized into independent regional and national bodies called Yearly Meetings which often split from one another because of doctrinal differences. Several federations for Yearly Meetings unite Quakers who share similar beliefs—for example Evangelical Friends Church International which unites evangelical Christian Friends,; Friends United Meeting which unites Friends into "fellowships where Jesus Christ is known, loved and obeyed as Teacher and Lord"; and Friends General Conference links groups that have liberal beliefs. Many Yearly Meetings are also members of Friends World Committee for Consultation, a loose international federation of Yearly Meetings from the different traditions.

Jan de Hartog (April 22, 1914 – September 22, 2002) was a Dutch playwright, novelist and occasional social critic who moved to the United States in the early 1960s and became a Quaker.

Jan de Hartog was born to a Dutch Calvinist Minister (and professor of theology), Arnold Hendrik, and his wife, Lucretia de Hartog (who herself was a lecturer in medieval mysticism), in 1914. He was raised in the city of Haarlem, Holland.

At around the age of 11, he ran away to become a cabin boy, otherwise referred to as a "sea mouse" onboard a Dutch fishing boat. His father had him brought home, but shortly afterwards, Jan ran off to sea again. The experiences thus gained became material for some of his future novels, as many of his life experiences did.

At 16, he briefly attended the Netherlands Naval College but was only there for a year. Per his own account, he was expelled, and told emphatically by his angry schoolmaster, "This school is not for pirates!"

De Hartog was a coal shoveler on the night shifts with the Amsterdam Harbor Police until 1932. As he often had time on his hands, he began to write here.

George Fox (July 1624 – 13 January 1691) was an English Dissenter and a founder of the Religious Society of Friends, commonly known as the Quakers or Friends.

The son of a Leicestershire weaver, Fox lived in a time of great social upheaval and war. He rebelled against the religious and political authorities by proposing an unusual and uncompromising approach to the Christian faith. He travelled throughout Britain as a dissenting preacher, for which he was often persecuted by the authorities who disapproved of his beliefs.

Fox married Margaret Fell, the widow of one of his wealthier supporters; she was a leading Friend. His ministry expanded and he undertook tours of North America and the Low Countries, between which he was imprisoned for over a year. He spent the final decade of his life working in London to organize the expanding Quaker movement.

Though his movement attracted disdain from some, others such as William Penn and Oliver Cromwell viewed Fox with respect. His journal, first published after his death, is known even among non-Quakers for its vivid account of his personal journey.