The company was founded by John Mitchinson, director of research for the British television panel game QI; Justin Pollard, historian and QI researcher; and author Dan Kieran.

[3][4] In 2016[5] Unbound launched a podcast called Backlisted, involving a guest (typically a writer) share a book they love and why it deserves more coverage.

In autumn 2017 Unbound launched Boundless, an online literary magazine with a focus on long form writing and tackling the decline in traditional media.

[6] In March 2021, the company announced a crowdfunder for 42: the wildly improbable ideas of Douglas Adams, a book based on Douglas Adams' papers, edited by Kevin Jon Davies.

[7] The book was published on 28 August 2023 (ISBN 9781800182684) and became a Sunday Times number one bestseller.