James Logan was born at Lurgan, County Armagh, on October 20, 1674. His parents were Patrick Logan (1640–1700) and Isabella, Lady Hume (1647–1722), who married in early 1671, in Midlothian, Scotland. His father had a Master of Arts degree from the University of Edinburgh, and originally was an Anglican clergyman before converting to Quakerism, or the Society of Friends. Although apprenticed to a Dublin linen-draper, he appears to have received a good classical and mathematical education, and to have acquired a knowledge of modern languages not common at the period. The War of 1689–91 obliged him to follow his parents, first to Edinburgh, and then to London and Bristol, England where, in 1693, James replaced his father as schoolmaster. In 1699, he came to the colony of Pennsylvania aboard the "Canterbury" as William Penn's secretary. Logan is described as "tall and well-proportioned, with a graceful yet grave demeanor. He had a good complexion, and was quite florid, even in old age; nor did his hair, which was brown, turn grey in the decline of life, nor his eyes require spectacles."